text:
|Publication number
|Publication type
|Application number
|Publication date
|Jun 28, 1994
|Filing date
|Jul 9, 1993
|Priority date
|Apr 30, 1993
|Fee status
|Also published as
|Publication number
|Stanford R. Ovshinsky, David V. Tsu, Rosa Young
|Original Assignee
|Energy Conversion Devices, Inc.
|Export Citation
|BiBTeX, EndNote, RefMan
|Referenced by (59), Classifications (23), Legal Events (5)
|External Links: USPTO, USPTO Assignment, Espacenet
This Application is a continuation-in-part of co-pending U.S. application Ser. No. 08/056,156 filed Apr. 30, 1993.
This invention relates generally to apparatus and methods used for the high-rate, low-temperature deposition of high quality thin film materials. The invention more particularly relates to a novel method for high-rate, low-temperature deposition of alloys and fabrication of devices therefrom by microwave PECVD from reaction gases. The improved method includes exciting microwave initiated plasmas by a combination of very low frequency ion cyclotron resonance (LFICR) and conventional microwave electron cyclotron resonance (MWECR). The pressure regime in which the deposition occurs is in the millitorr range so as to provide an ultra-clean deposition environment to prevent the deposition of contaminants.
While the discussions and detailed descriptions of the present invention set forth hereinbelow have been primarily directed toward the deposition of thin films of amorphous semiconductor material, it should be noted that the present technique can be used for the high-rate, low temperature deposition of many other materials. Particularly, the method can be used to deposit materials whose total microstructural local environment includes amorphous, nanocrystalline, microcrystalline, polycrystalline and monocrystalline as well as combinations thereof and intermediate metastable states. The materials which may be deposited by the method of the present invention are not limited to semiconductors, but can also include metals, ceramics, glasses, polymers, dielectrics, insulators and photoactive materials. Of particular interest are semiconductors, high density oxides and nitrides, conductive metals and ceramic protective coatings. Also of interest are nanocrystalline materials having grain features of 30 Angstroms or less.
Another example of a field of particular interest, other than semiconductor materials, is metallic aluminum and/or copper conductive pathway deposition for ultra large-scale integration (ULSI) of electrical circuits. Today, as integrated circuit technology strives for higher and higher integration densities, the width of the electrical current carrying pathway required to achieve these integration densities has become much smaller. In the present state of the technology, there is difficulty with the physical vapor deposition process by which such narrow conducting lines are formed by conventional sputtering techniques. Deposition of conductive pathway material into the openings in the photolithographic masking, which are sometimes as small as nanometers wide, causes a shadowing problem. That is, because PVD produces non-conformal coverage, which leads to thinning at the edges and walls of vias and trenches and to big holes in vias. Therefore, there is a limit to the narrowest effective width to which the conductive pathways can be deposited, without forming open circuits therein.
In general, CVD offers better coverage conformality than PVD. Given the chemical vapor deposition method of the present invention, the depositing species can have a much higher surface mobility, and can therefore "fill in" the shadowed areas, thereby effectively extending the lower limit on the narrowest effective width to which conductive pathways can be deposited.
Prior to turning to the use of the novel method disclosed herein for depositing high quality amorphous silicon alloy material, it is significant to elucidate the reader as to the full capabilities of this method to deposit new and phenomenally different quantum mechanical materials.
A considerable effort has been made to develop processes for readily depositing amorphous semiconductor alloys or films, each of which can encompass relatively large areas, if desired, limited only by the size of the deposition equipment, and which could be readily doped to form p-type and n-type materials where p-n junction devices are to be made therefrom equivalent to those produced by their crystalline counterparts. Amorphous silicon or germanium (Group IV) films are normally four-fold coordinated and were found to have microvoids and dangling bonds and other defects which produce a high density of localized states in the energy gap thereof. The presence of a high density of localized states in the energy gap of amorphous silicon semiconductor films results in a low degree of photoconductivity and short carrier lifetime, making such films unsuitable for photoresponsive applications. Additionally, such films cannot be successfully doped or otherwise modified to shift the Fermi level close to the conduction or valence bands, making them unsuitable for making p-n junctions for solar cell and current control device applications.
A reduction of the localized states was accomplished by glow discharge deposition of amorphous silicon films wherein a gas of silane (SiH4) was passed through a reaction tube where the gas was decomposed by an r.f. glow discharge and deposited on a substrate at a substrate temperature of about 500�-600� K. (227�-327� C.). The material so deposited on the substrate was an intrinsic amorphous material consisting of silicon and hydrogen. To produce a doped amorphous material a gas of phosphine (PH3) for n-type conduction or a gas of diborane (B2 H6) for p-type conduction were premixed with the silane gas and passed through the glow discharge reaction tube under the same operating conditions. The gaseous concentration of the dopants used was between about 5�10-6 and 10-2 parts per volume. The material so deposited included supposedly substitutional phosphorus or boron dopant and was shown to be extrinsic and of n or p conduction type.
Amorphous semiconductor alloys made by the prior art processes have demonstrated photoresponsive characteristics ideally suited for photovoltaic applications. These prior art processes however suffered from relatively slow deposition rates and low utilization of the reaction gas feed stock which are important considerations from the standpoint of making photovoltaic devices from these materials on a commercial basis. To alleviate the problem of slow deposition rate, a microwave plasma deposition processes was invented by Ovshinsky, et al. See U.S. Pat. No. 4,517,223, Method of Making Amorphous Semiconductor Alloys and Devices Using Microwave Energy, which issued on May 14, 1985, the disclosure of which is hereby incorporated by reference. The microwave plasma process herein provides substantially increased deposition rates and reaction gas feed stock utilization. Further, the microwave process resulted in the formation of reactive species not previously obtainable in sufficiently large concentrations with other processes. As a result, new amorphous semiconductor alloys could be produced having substantially different material properties than previously obtainable.
The principal advantage that microwave (e.g., 2.45 GHz) generated plasmas have over the more widely used radio frequency (e.g., 13.56 MHz) generated plasmas is that the thin film deposition rates are generally higher by factors of 10 to 100. This enhanced rate comes about because of the increased fraction of all the electrons in the plasma which have the necessary energy to be chemically relevant, i.e., energies greater than about 3 to 4 eV in which to excite molecules, and especially energies greater than 8 to 12 eV in which to dissociate and/or to ionize molecules. In other words, for the same power densities, microwave plasmas are more effective in generating the chemically active species (i.e., excited molecules, dissociated, very reactive radicals, ions, etc.), which are necessary to form thin films, than are radio frequency plasmas. One obstacle that has prevented thin film microwave plasma deposition from being more widely used is that the thin film material properties (e.g., electronic, density, etc.) tend to be inferior to those deposited by radio frequency plasma.
More recently, dual-frequency plasma deposition has been investigated as a method for simultaneously combining the advantageous features of both microwave and radio frequency plasma depositions. That is, while microwave plasma is very efficient for generating active species in the gas phase (because of a relatively higher population of electrons in the energetic tail of the electron energy distribution function), resulting in deposition rates an order of magnitude higher than those observed at lower frequencies, the quality of the deposited material is lacking. On the other hand, radio frequency plasma is characterized by a negative d.c. bias at the cathode, which controls the flux and energy of ions impinging on the cathode surface, resulting in high quality thin film deposition, but at very low deposition rates. Dual-frequency plasma deposition using both microwave energy at 2.45 GHz and radio frequency energy at 13.56 MHz has been shown to produce better quality thin films than microwave energy alone at a higher deposition rate than radio frequency energy alone. See Klemberg-Sapieha et al, "DUAL MICROWAVE-R.F. PLASMA DEPOSITION OF FUNCTIONAL COATINGS", Thin Solid Films, vol. 193/194, December, 1990, pages 965-972.
Although this dual-frequency (DF) plasma deposition method clearly has advantages over single frequency microwave (MW) or radio frequency (RF) plasma, it clearly only a compromise. While DF plasma has higher deposition rates than RF plasma, the rates are unquestionably lower those of MW plasma. Also, while the quality of DF plasma deposited films is greater than those deposited by MW plasma, it is undoubtedly lower than those deposited by RF plasma. It has been found that at the higher deposition rates of MW plasma deposition, it becomes increasingly important that the active neutrals (i.e. chemically activated, electrically neutral species) have higher kinetic energy so that when they arrive at the film surface, they will have the necessary surface mobility to create a high quality film.
In the discussion of microwave plasma deposition above attention should be focused on the electrons, for it is the electrons, which excite, dissociate and ionize the gaseous molecules. One possible mechanism why microwave energy leads to higher electronic energy in the plasma is that the electrons can resonantly couple to the energy. For example, in typical microwave plasmas, the electron density can range from 1010 to 1011 per cm3. At these densities, the resulting plasma oscillation frequency is on the same order as the applied radiation, namely in the low GHz range. Although a tremendous amount of the energy of the high frequency radiation can be pumped into the electrons by resonantly coupling, little if any of that energy can be transferred into kinetic energy of the ions and neutral molecules. This is because the ions are too massive to respond to the high frequency oscillations of the microwave and/or radio frequency energy, and also the energy gain of the electrons cannot be effectively transferred to the ions/neutrals due to the their large difference in mass.
There are two ways to resonantly couple energy into a plasma: (a) by high frequency radiation, which couples into the electrons; and (b) by low frequency radiation, which couples into the ions. When energy is pumped into the ions, their energy is very effectively transferred into the neutrals owing to their similarity in masses. Heating of the neutrals is desirable because it is the neutrals which overwhelmingly account for the deposition rate. It should be noted that because a relatively few ions must heat a large number of neutrals, efficiency requirements dictate the need to resonantly couple energy into the ions.
Large scale uniform deposition in rf plasma systems is not a serious issue because the wavelength at 13.56 MHz is more than 22 m, i.e., much greater than any practical deposition chamber. However, since the wavelength at the microwave frequency of 2.45 GHz is only 12.2 cm, the technical challenges in achieving uniform depositions over the desired scale of 30 cm are evident. Because of this, deposition results (e.g., film quality from a certain point in parameter space) obtained from small sized microwave research reactors (˜5 cm substrates), cannot be automatically applied to the larger production systems because the hardware implementation will be fundamentally different. Scaling the process to larger sizes is not simply a matter of making larger electrodes (as it is in rf plasma systems) but involves new concepts. Although others have demonstrated high quality a-Si:H films with solar cell efficiencies approaching the best rf deposited material, similar results on the large production scale have yet to be demonstrated.
The record efficiency of 13.7% (active area, initial efficiency) for a multijunction a-Si alloy cell from PECVD was reported in 1988 by J. Yang et al. of ECD Proceedings of the 20th IEEE PV Specialists Conference (1988) page 241. Since then, progress has only been made in improving the large area module efficiency, which has now reached the initial efficiency of 10-11% and stable efficiency of 9-10%. The lack of progress in improving the quality of the narrow bandgap (Eg <1.5 eV) a-SiGe alloy as well as the wider bandgap a-SiC alloys (eV>1.8 eV) is the primary reason preventing further efficiency enhancement. In order to reach the DOE goal of a stable 15% efficiency for modules by the year 2005, a major breakthrough of materials on either narrow bandgap a-SiGe alloy material or wider bandgap a-SiC alloy materials has to be made. The glow discharge technique which has been very successful in fabricating high quality a-Si:H has not been able to provide equivalently high quality material where the base alloy has been modified to widen or narrow the bandgap. Simply stated, the photovoltaic properties of the alloys severely deteriorate with increasing Ge or C content.
Generally, the film quality of a-SiGe alloys, as characterized by the defect density measured from sub-bandgap absorption, the network disorder measured from the Urbach parameter and the photosensitivity (σlight σdark), deteriorate with increasing Ge content. The deterioration of the material quality severely affect the fill factor (FF) of the devices. As the Ge content of the intrinsic layer of a PV device exceeds 40% (i.e., Eg <1.5 eV), the FF becomes so poor that no decent device can be made. To maintain a good FF (˜0.7), the current multijunction solar cell can only use materials with 1.5 eV≦Eg ≦1.75 eV. Should the narrow bandgap 1.2 eV<Eg<1.5 eV a-SiGe alloy be made of a quality which approaches that of an a-Si:H alloy, a multijunction laboratory device would have an efficiency of ≧17% (i.e. Voc=2.5 V, FF=0.75 and Jsc>9 mA/cm2) and a 15% stable module efficiency could be obtained.
In a conventional PECVD system, the gas phase environment contains electrons, various types of ions, chemically active neutral species (i.e. free radicals) and molecules. At an operating pressure of 0.5-1.0 Torr the degree of ionization is extremely low (i.e. <10-6). Therefore, only the free radicals contribute to the film growth. Electrons, due to their light mass, gain energy from the electric field much more effectively than the heavier ions. The electron energy distribution can be roughly described as a Maxwell-Boltzmann distribution with average electron energies around 2 eV, corresponding to an electron temperature of ˜104 K. Since the ions are able to receive some energy from the field, their temperature is slightly above ambient. The typical ion energy is around 0.04 eV or ˜500 K. Because of the low degree of ionization, and the low ion energy, the neutral free radicals remain essentially at ambient temperature. In other words, the kinetic temperature of the film precursors from conventional PECVD processes is around 0.025 eV or 300 K.
In any deposition process, the surface mobility of the precursor species is a critical parameter in determining the quality of the depositing film. It is important that the precursor species, upon their arrival at the surface, be able to move around to find energetically favored sites and to fill microvoids. Since the film precursors from PECVD are not energetic, the precursor primarily rely on the substrate temperature (Ts) as the energy source. Unfortunately, the Ts of hydrogenated amorphous films are limited by the hydrogen evolution temperature which is much lower than the crystallization temperature. For example, the crystallization temperature of silicon is ˜630� C., whereas hydrogen evolution from the a-Si:H film begins at a temperature of about 250�-275� C. Films deposited at Ts above 275� C. from a conventional PECVD system will have a higher number of dangling bonds due to hydrogen evolution. In the case of a-SiGe:H film deposition, because the bond strength of Ge-H is weaker than Si-H, hydrogen evolution from Ge begins at 150� C. To prevent the preferential loss of hydrogen, one would expect that the film should be deposited at a Ts of ˜150� C. However, experiments indicate that device performance of a-SiGe film deposited at Ts of ˜150� C. is rather poor. Most of the so called "device quality" a-SiGe alloys with Eg ≧1.5 eV are actually deposited at ˜300�-325� C. As a result, the narrow bandgap films have a higher dangling bond density than the a-Si:H films.
Why do the a-SiGe alloys prefer to grow at higher temperatures, despite hydrogen evolution? One possibility is that Ge precursors in the plasma are less mobile than Si precursors because the Ge atom is bigger and heavier than the Si atom. In order for Ge to move as freely as Si on the growing surface, a higher Ts is desirable. If not for H evolution, higher quality a-SiGe films might be grown at even higher temperatures. This argument also explains why the quality of the depositing film deteriorates with increasing Ge content, i.e., because at temperatures of 300�-325� C., the preferential loss of H from Ge sites is aggravated.
The lack of surface mobility in the depositing a-Ge:H film is also manifested by the high degree of disorder in the network and high porosity present in the deposited films. If the precursor species were mobile, they would have a greater opportunity of finding low energy sites so that not only a denser film could be made, but better, stronger bonds could be formed. Thus, increasing surface mobility of depositing species will lead to a reduction of weak bond formation and elimination of the Stablaer-Wronski effect. In the case of a-Si:H film growth, high quality material is typically deposited at a rate of 1-2 Å/sec at 250� C. The quality of the film deteriorates with increasing deposition rate. Since surface diffusion is a rate-limiting process, this result indicates that at 250� C., even the Si precursors can barely move fast enough to accommodate even low rate deposition. Should the surface mobility of Si precursors be further enhanced without increasing Ts, it would enable high quality a-Si:H alloy material to be deposited at much higher rates, even up to 100 Å/sec. High rate deposition translates into high production throughput and lower production costs.
From the above discussion, it becomes clear that one of the fundamental problems in the deposition of high quality a-SiGe films is fighting the conflicting growth parameters of surface mobility and hydrogen evolution.
Since fluorine bonds to Ge much more strongly than H, one would expect that the temperature fluorine evolution from Ge should be much higher than that of H from Ge. This is one reason to use a fluorine containing gas as precursor in the a-SiGe alloy deposition. However, a fluorine passivated surface is not as "slippery" as a H covered surface, because F is so reactive that it bonds too readily with film precursors at the first point of contact. Therefore, the a-SiGe:F film has more network disorder than an a-SiGe:H film. Nevertheless, it has been demonstrated that small amounts of F does help in making higher quality films.
Since there has not as yet been a way found to use F to replace H, and since the substrate temperature cannot be raised without H evolution, the only viable solution for depositing high quality a-SiGe film seems to be raising the kinetic temperature of the precursor species. As was pointed out previously, the kinetic temperature of the precursor species in PECVD is virtually ambient and the species will be heated at most to the substrate temperature. Clearly this temperature is not high enough.
Described hereinbelow are several unique features of PECVD which are important to a-Si and a-SiGe growth. First, there is an abundance of atomic hydrogen in the plasma. The atomic hydrogen on the growing surface can remove weak bonds and passivate dangling bonds. Hydrogen is needed in the structure not only to passivate dangling bonds, but to release strain in the tetrahedrally bonded amorphous network. Secondly, the dominant film precursor for a-Si:H deposition from PECVD is generally believed to be SiH3. This is due to the low reactivity of SiH3 with the primary discharge gases such as H2 and SiH4, which allows it to diffuse to the substrate surface. The advantage of such a low reactivity precursor is that it will have a small probability of surface reaction at the initial point of contact, and thus requires less energy to move around on that surface. This may be one of the reasons that PECVD a-Si:H exhibits the best photovoltaic properties compared to films deposited by other techniques. By analogy to silane chemistry, it is expected that GeH3 is the dominant precursor for a-Ge:H film. However, GeH3 is much heavier and diffuses slower than SiH3. Hence, an a-Ge:H film is much more porous and of poorer quality than an a-Si:H film under the same deposition conditions. Finally, even though free radicals such as SiH, SiH2, SiH3, etc. are unable to gain kinetic energy, through elastic collisions with electrons, they can acquire quite high internal energy, in the form of vibrational and rotational energy, through various inelastic collision processes. For example, the vibrational and rotational temperatures of the free radical SiH have been measured from the intensity of the optical emission spectrum. In the electronically excited state, the temperatures are 4000 K. and 1800 K., respectively. In the ground state, they are 2000 K. and 485 K., respectively. The high internal energy of free radicals is another special feature of PECVD. It had been speculated that because of the high internal energy of free radicals, microcrystalline films can be grown at temperatures below 200� C.
In a-Si:H and/or a-SiGe:H film growth, the precursor species such as GeH3 and/or SiH3 arrive at the surface, move around, and locate the most energetically favorable low energy sites, thus forming a thin film on the substrate. Hydrogen elimination and a restructuring of the surface bonds will proceed to complete the growth process. However, energy is required for these processes to occur. The high internal energy of the precursor species may be an important energy source for the successful initiation of these processes. Therefore, techniques which solely heat the gas to increase the translational temperature of the precursor species cannot ensure the fabrication of high quality film. A number of aspects which are critically important to film growth in PECVD can be identified. For example, the abundance of atomic hydrogen, the low reactivity of precursor species and the high internal energy of those species are all important attributes in the growth of a-Si:H and a-SiGe:H films and should be present in the any advanced PECVD technology. A drawback with conventional embodiments of PECVD is the low kinetic temperature of the precursor species which have prevented the growth of high quality a-SiGe alloy films.
Therefore, there is still a strong felt need in the art for a safe method for the high-rate, low-temperature deposition of high-quality materials on large area substrates.
One aspect of the present invention is a microwave enhanced chemical vapor deposition method for high-rate, low-temperature deposition of thin film material. The method includes the steps of providing an evacuated chamber having a plasma deposition region defined therein; placing a substrate inside the chamber; supplying plasma deposition precursor gases to the deposition region in the evacuated chamber; directing microwave energy from a source thereof to the deposition region, the microwave energy interacting with the deposition precursor gases to form a plasma of electrons, ions and activated electrically neutral species, the plasma including one or more depositing species; increasing the surface mobility of the depositing species in the plasma by coupling additional non-microwave electronic energy and magnetic energy into the plasma, without intentionally adding thermal energy to the substrate or precursor gas; and depositing a thin film of material onto the substrate.
It is additionally useful to control the ratio of species, relative to one another in the plasma, particularly the ratio of ions to active neutrals, to prevent ion damage of the depositing thin film while also achieving the increase in surface mobility of the depositing species. Preferably, the magnetic energy is a magnetic field which is coupled to the microwave energy so as to provide electron cyclotron resonance, and the magnetic field should be 875 Gauss within the plasma when coupled to microwaves having a frequency of about 2.45 GHz. Also, the non-microwave electronic energy is preferably a low frequency alternating electrical field having a frequency of less than about 1 MHz, the frequency of the low frequency alternating electrical field creating an ion cyclotron resonance condition for one or more groups of ions in the plasma, under the influence of the magnetic field. While the precursor gases need only include those materials desired in the deposited thin films, they will typically include one or more of GeH4, GeF4, SiH4, SiF4, F2, and H2, and also may include inert, non-depositing gases such as argon or helium, when depositing silicon, germanium or silicon-germanium alloy materials. Useful frequencies for the low frequency alternating electrical field are about 18.5 kHz to induce ion cyclotron resonance for the Ge group of ions and about 48 kHz to induce ion cyclotron resonance for the Si group of ions. The microwave energy may be supplied at a power of between about 2 and about 5 kiloWatts and the low frequency alternating electrical field may be supplied at a power of between 0.1 and 1.0 kiloWatts.
The magnetic energy may be supplied by either permanent magnets or electromagnets placed in close proximity to the deposition region and the non-microwave electrical energy is supplied by antenna electrodes also placed in close proximity to the deposition region. Typical materials which can be deposited by the present method are metals, ceramics, polymers, glasses, semiconductors, photoconductors, dielectrics, oxides and nitrides, or any other material which is known to be depositable by conventional PECVD. Particularly, the method can be used to deposit materials whose total microstructural local environment includes amorphous, nanocrystalline, microcrystalline, polycrystalline and monocrystalline as well as combinations thereof and intermediate metastable states. The precursor gases used to deposit the desired material are chosen to provide the required depositing species to form the desired thin films on the substrates. One exemplary area of interest are amorphous semiconductors.
Additional objectives and aspects of the instant invention will be obvious from the detailed description, claims and drawings appended hereto.
FIG. 1 is a graphical presentation illustrating the normalized distribution of number of germanium ions (mass=73 amu) that have an orbital length between L and L+0.1 mm in an external magnetic field of 875 Gauss, plotted on the ordinate versus the orbital path length L in mm plotted on the abscissa, the distributions are plotted for three temperatures 500�, 1000� and 1500� C.;
FIG. 2 is a partial schematic diagram, not to scale, of a microwave deposition apparatus useful for performing the method of the present invention, specifically depicting an improved vacuum feed-through and an improved linear applicator;
FIG. 3 is a top view, not to scale, of an improved linear microwave applicator useful in an apparatus for performing the method of the present invention, specifically illustrating microwave reflecting panels;
FIG. 4 is a partial side view, not to scale, of the microwave wave guide portion of the linear microwave applicator useful in performing the method of the present invention, specifically illustrating the rectangular wave guide portion of the applicator and the microwave radiative slot formed in one of the wider faces thereof; and
FIG. 5 is a cross sectional side view, not to scale, of a microwave vacuum feed-through useful in an apparatus for performing the method of the instant invention, specifically illustrating the microwave transmissive plates and the vacuum seals for isolating the interior vacuum from the exterior atmosphere.
To begin with, a brief discussion of the energy transfer mechanism in the plasma will be useful. The particles in a plasma usually have two types of energy: kinetic energy due to their motion and internal or potential energy which may be in various forms of electronic energy such as excitation, dissociation, and ionization energies. These energies are normally expressed in terms of eV or temperature (Note 1/40 eV equals ˜300 K.). Energy can be transferred through either elastic or various forms of inelastic collisions. An elastic collision is one in which there is an interchange of kinetic energy only. An inelastic collision has no such restriction, and internal energies will also change. At high excitation frequencies (>1 MHz) only electrons can follow the applied AC field and gain energy, ions are essentially immobile. Therefore, in a conventional RF (13.56 MHz) or MW (2.45 GHz) plasma, energy transfer primarily involves neutral and ionic species colliding with electrons. However, the kinetic energy transfer from electrons to neutrals through elastic collisions is negligible due to the large difference in masses. Importantly, neutrals can gain internal energy from inelastic collisions as has been described previously. But, neutrals can only gain kinetic energy through elastic collisions with ions, preferably of similar mass, provided: (1) the degree of ionization is high so that there is a high probability of elastic ion-neutral collision; (2) the ions have the right amount of energy to transfer; and (3) the ions can regain their energy after each collision.
Our approach to energize the neutrals is to combine two resonance techniques in the PECVD system, i.e. the electron cyclotron resonance (ECR) and the ion cyclotron resonance (ICR). The microwave ECR (MWECR) technique has been developed over the years as a commercial technique for plasma ion etching and film deposition. The advantages of MWECR is that it is an electrodeless, low pressure process which produces a high degree of ionization. However, the kinetic temperatures of ions and neutrals remain low. Therefore, in addition to MWECR, a low frequency ion cyclotron resonance (LFICR) needs to be added to accelerate ions and thereby transfer energy to neutrals.
Electronic excitation of molecules at MW frequencies is notably more effective than at lower frequencies. This is because of the way in which MW radiation is resonantly absorbed. Note, in particular, the two resonant absorption mechanisms. The first mechanism involves elastic electron-neutral collisions; at sufficiently low energies (e.g., below molecular or atomic excitation levels), electrons will elastically collide with neutral gas species. If each collision coincides with an electric field reversal, the electron can continue to gain energy. Because of the low mass and high velocity of the electron, the collisional frequency tends to be in the GHz range. MW energy can be coupled to these collisions. The second mechanism involves plasma oscillations. The plasma oscillation is specifically related to properties of the plasma itself. In plasmas that are typically achieved in PECVD, the electron density is ˜1010 cm-3. At these densities, the resulting plasma oscillation frequency is in the upper MHz to lower GHz range. MW radiation can also resonantly couple energy into these plasma oscillations. However, the MW energy coupling is very pressure dependent. Efficient energy coupling would occur in the pressure range of ˜1-10 Torr depending on the gases used for the glow discharge plasma. With 2.45 GHz excitation frequency, the plasma density is usually limited by a critical density of 7.2�1010 cm-3. This results in a degree of ionization of <10-5, which is too low for the purpose of our experiment. In order to achieve a high degree of ionization (˜1-10%), a more efficient energy coupling mechanism in a lower pressure system is required. This is the reason to use MWECR. In ECR, microwave energy is coupled to the natural resonant frequency of the electrons in the presence of a static magnetic field. This resonant frequency occurs when the electron cyclotron frequency, which is defined as:
ω=eB/m (1)
(where e=charge of an electron, B=strength of a static magnetic field and m=mass of the charged particle) equals the excitation frequency of 2.45 GHz. To create the ECR volume, a magnetic field strength of 875 gauss is required. The electrons are then accelerated from the MW energy in this ECR volume and in turn ionize and excite the neutrals much more efficiently than in a conventional MW system. Because of the ECR resonance, very efficient coupling can occur, even at pressure as low as 0.1 mTorr. For example, at 1 mTorr argon pressure the plasma densities can be as high as 5�1012 cm-3, and the degree of ionization increases to the 20%-25% range.
Although a high degree of ionization can be achieved in MWECR, the kinetic temperature of ions as well as neutrals remains low. In order for the neutrals to gain kinetic energy, the ions must gain the energy first. This is one reason to add LFICR to the MWECR microwave deposition process.
With the presence of a static magnetic field in the system, not only will electrons move in a cyclotron motion around the magnetic field with a electron cyclotron frequency, ions will also cirulate around the field with an ion cyclotron frequency. However, because of the heavier mass, the ion cyclotron frequency is much lower than electron cyclotron frequency. With the same magnetic field, i.e., 875 G for ECR, the ion cyclotron frequency of H, Si and Ge calculated from equation (1) are listed below:
______________________________________Atom M(amu) ICR frequency______________________________________H 1 1.34 MHzSi 28 48.0 kHzGe 73 18.5 kHz______________________________________
With such low ion cyclotron frequencies, virtually no MW energy can be absorbed by the ions. Therefore, a low frequency (LF) modulation must be imposed to resonantly couple energy to the ions. The distinct and separate ICR frequency of these ion groups also offer the possibility of directly targeting a specific ion for resonant heating. For example, an 18.5 KHz modulation frequency will resonantly heat the Ge ion group such as Ge+, GeH+ etc. more effectively than the Si and H ion groups. It is important to realise that for the greatest increase in the kinetic energies of the active neutrals, the LF frequency should be chosen to cause ICR conditions in the ion group of the heaviest of the depositing species (i.e. largest energy transfers occur between masses of like size). That is, for example, in the deposition of Si-Ge alloys from silane and germane, the ICR frequency should be chosen to correspond to that required to resonate Ge group ions. However, if the heaviest depositing species in too small of an atomic percentage of the total, the next heaviest ion group should be chosen. This is because too low of a ratio of resonating ions to total neutrals will result in low energy transfer to the neutrals.
It should be noted that while the invention is herein described in terms of microwave energy at 2.45 GHz (which then fixes the magnetic field required for ECR and the frequency required for ICR), other commercial microwave frequencies exist (such as 915 MHz) which may be used in PECVD. This then would require a different magnetic field strength and different low frequency energy frequency to produce ECR and ICR.
Two principle methods by which the low frequency (LF) modulation can be imposed are capacitive couple and inductive coupling. With capacitive coupling, the electric field is applied using electrodes. However, in this type of coupling, the high electric potential of the electrode will impose its voltage on the plasma, i.e., a high plasma potential is developed. This potential depends somewhat on electrode geometry and usually is in the range of 50-100 volts. Note that in the microwave excitation of plasmas, the plasma potential will be much lower because there is no electrode. In the MWECR plasma system, because of the high degree of ionization, any high plasma potential developed from the added electrode should be avoided.
Other than the high plasma potential, the electric field from the capacitive technique cannot be effectively coupled to ions in the bulk of the plasma. Because plasmas are very good conductors, it is very difficult to directly expose an ion inside a plasma to an externally applied electric field. Debye shielding effectively screens the field. The only place in the discharge that electric fields exist is in the plasma sheath region. Unfortunately, for the plasma, ion acceleration in the sheath does not contribute to the thermal energy of ions in the plasma. This is because the ions accelerate away from the plasma toward the electrodes. In addition, those accelerated ions may cause sputtering and ion damage and do not significantly contribute to heating the neutrals because ion-neutral scattering is small in the sheath region (the mean free path is relatively long at low pressures (≦10 mTorr)). In other words, at low pressures, the plasma sheath is approximately collisionless. For these reasons, we conclude that low frequency modulation by capacitive coupling technique is not suitable.
Since the use of inductive coupling does not require the use of electrodes, the plasma potential will remain at the low levels of the unmodulated case. Inductive excitation is a commonly used technique to generate plasmas in plasma torches. Inductive excitation utilize a water cooled copper coil of a few turns. Since each turn can be considered a separate current loop, the induced time varying magnetic field vector has components both in the axial and radial directions, while the electric field vector is primarily in the tangential direction. This electric field then results in an electrical current (J=σE) which circulates around the axial magnetic field. The penetration of this electric field into the plasma region, i.e., the skin depth, depends on the plasma density, the electron collision rate, and inversely on the applied frequency. In plasma torches operated at atmospheric pressure, the plasma density is in the 1018 cm-3 range and the skin depth has been estimated to extend a few mm. However, in the case of a low temperature plasma with a plasma density of 1012 cm-3 and frequencies in the range of 1-100 KHz, calculations show that the skin depths is in the range of 2�104 to 20 cm. Dimensions of these magnitudes are greater than the plasmas of interest. This means that the induced electric fields from the inductive coupling technique can penetrate the entire bulk of the plasma and accelerate the bulk ions and heat the neutral species. Unlike capacitive coupling, the inductive currents (both electrons and ions) do not leave the plasma region, but continually circle within it. Inductive coupling therefore provides a much more effective coupling mechanism.
One of the important aspects to achieving resonance is the ability of the ions to complete at least one cyclotron orbit. If the charged species collides with another particle before completing the orbit, resonance coupling will be lost and the heating effectiveness will be reduced. This is why the ECR condition requires gas pressures lower than about 10 mTorr. The question is whether it is possible for ions to make one complete orbit before colliding with a neutral gas species, i.e., whether the orbital path length (L) is less than the mean free path (λ) for a collision to occur. Note, there exists an optimum λ/l ratio (r) that results in the most effective heating of the gas. In terms of r, the ion will be able to orbit a certain number of times, acquiring the energy of
Σ=er∫E�dL (2)
before it collides, where the integral is over one orbit. So, for very large r (r>>1), the total energy gained will be very large. But in this case, most of the neutral species have bypassed the orbiting ion, thus limiting the effectiveness of transferring energy to the majority of neutral species. If, on the other hand, r is small (r<1), the ion-neutral transfer rate is high, but the energy per transfer is very low. Again, the total transfer of energy is low because the acquired energy of the ion is low. It is clear that an intermediate value of r exists that optimizes the transfer of ionic energy to the neutral species. This optimal r will depend on the magnitude of the electric field (E), i.e., on the power of the LF radiation. So for a fixed E, r can be controlled by varying the gas pressure, and will be different for ions of different mass. This is examined below.
It is important to note that the ratio of the species (electrons, ions and active electrically neutral species), relative to one another, in the plasma should be controlled. Particularly, the ratio of ions to active neutrals should be controlled. The reason for this control is to allow for the required increase in the surface mobility of the depositing species, while also preventing damage to the depositing thin film by excessive ion bombardment/deposition when the substrate is close to the ECR/ICR region of the plasma.
As is alluded to herein, one method of controlling the ratio of ions to active neutrals (also known as the ionization factor of the plasma) is by controlling the deposition pressure. Another means of increasing the probability of transferring kinetic energy from ions to neutrals, especially at lower ionization factors, is by increasing the total volume of the ECR/ICR zone and therefore, the probability of collision.
To compare the most probable orbital path length of a given ion at a given ion temperature with the mean free path, first determine the energy dependence of the ion cyclotron radius (R):
R=v M/(eB)=(2ε/M)1/2 M/(eB)=(2εM)1/2 /(eB)(3)
The orbital path length is then:
L=2π(2εM)1/2 /(eB)=a(εM)1/2 (4)
where a=10.33 for a fixed field of 875 Gauss (which is required for ECR), ε is in eV, and M in amu. If it is assumed that the ions are initially thermalized, then the ions follow the Maxwell-Boltzmann energy distribution function F(ε). The probability of finding a particle in a range of energy dε, is
dn(ε)=F(ε)dε=2/{π1/2 (kB T)3/2 }ε1/2 exp [-ε/(kB T)]dε (5).
The energy probability function, Eq. (5), can be transformed using Eq. (4) to obtain the orbital probability function. The result is
dn(L)=4/{π1/2 (a2 MkB T)3/2 }L2 exp [-L2 /(a2 MkB T)]dL (6).
FIG. 1 is a graphical presentation illustrating the normalized distribution of the number of germanium ions (mass=73 amu) that have an orbital length between L and L+0.1 mm in a magnetic field of 875 Gauss, plotted on the ordinate versus the orbital path length L in mm plotted on the abscissa. FIG. 1 shows the temperature behavior of the orbital path length for Ge at 500, 1000, and 1500 C. The average orbital path length is readily determined from Eq. (6) to be
<L>=2a(MkB T/π)1/2.
Typical values of <L> for the ions at various temperatures are summarized below for a B field of 875 Gauss.
______________________________________ 25 500 1000 1500Temp. (C.) <L> <L> <L> <L>Ions (mm) (mm) (mm) (mm)______________________________________H 1.87 3.01 3.86 4.56Si 9.89 15.89 20.44 24.12Ge 15.97 25.7 33.00 38.94______________________________________
Rough estimates for the mean free path can be determined since the atomic diameters (d) are bounded roughly between 0.1 and 0.3 nm for atoms between atomic H and Ge. Since the mean free path is given by:
λ=kB T/(P A 21/2) (7).
where the area A=πd2. Typical values are tabulated below at room temperature. Note that at higher temperatures, the λ will increase.
Collisional mean free path at room temperature.
______________________________________ P = 1 mTorr 10 mTorrd(nm) A (nm2) λ (mm) λ (mm)______________________________________0.1 0.031 694 69.40.2 0.125 174 17.40.3 0.283 77 7.7______________________________________
A comparison of the foregoing reveals that even for an ion as heavy as Ge, for pressures between 1 and 10 mTorr, the mean free path is longer than the ion cyclotron orbital path. Therefore, the resonance condition is met.
Previously, the possibility of targeting the LF energy to a specific ion group was mentioned. In the case of ICR however, it is the ion cyclotron frequency as described in Eq. (1) that is mass dependent. The preceding discussion is tied together by giving an example of how this mechanism works, in particular, the resonance is described. One of the important points to clarify is the response of the other ions. For Ge ions, the LF should be tuned to 18.5 KHz for a magnetic field of 875 Gauss. Remember that the magnetic field strength was determined by the need to establish an ECR condition. Because the phase of the driving force is constant relative to that of the orbiting Ge ion, the ion will continue gaining energy until scattered by a collision. At room temperature and at a pressure of 1 mTorr, the Ge ion will be able to make 4.8 (=77/16) revolutions, on average, before a collision occurs. Meanwhile, the H ions are also orbiting around the magnetic field at a rate of 1.34 MHz. Moveover, these ions will be able to make roughly 371 (=694/1.87) revolutions before any collisions will occur. Two points should be made: (1) first, since the applied frequency is not 1.34 MHz, each revolution will result in a negligible net gain of energy; and (2) second, the 18.5 KHz electric field will result in a drift in the entire orbit of the H ion, but this drift will also not gain energy.
This technique increases and controls the kinetic temperature of neutral species. It should be pointed out that the kinetic temperature of, for example, GeH3 at 1000� C. will not cause gas phase decomposition and/or hydrogen evolution at the substrate. At the low operation pressure (≦10 mTorr), the bimolecular reaction rate is extremely low even at such elevated temperatures. This is because of the small bimolecular collision rate at these pressures. Furthermore, the kinetic temperature is not a thermal equilibrium temperature. At the surface, the reaction time is very short and will not cause hydrogen evolution.
Microwave excited PECVD has been attractive for a-Si:H deposition because of the high deposit rate. It is also because of the high rate deposition that the film quality is not as good as films deposited from a low-rate RF plasma system. With the dual resonance PECVD system proposed herein, the surface mobility of the precursor species can be enhanced without concerns over hydrogen evolution.
In a plasma with a high degree of ionization, the acceleration of ions toward the substrate generated from any DC field should be avoided. Since there is no electrode in the system, the plasma potential is much lower than in a comparable capacitively coupled PECVD system. Furthermore, the ions will be confined around the magnetic field lines which run parallel to the plane of the substrate. Therefore, ion damage on the film is minimized.
It should be noted that typically, the substrate upon which the thin film is being deposited is outside the ECR/ICR magnetic region and is therefore not highly bombarded by ions, and therefore, the ion damage can be avoided in this manner. Also, the distance between the ECR/ICR region and the substrate can be adjusted to vary the types and ratios of depositing species. For example, in a Si-Ge alloy deposition, if the substrate is closer to the ECR/ICR region, then the ratios of GeH/GeH3 and SiH/SiH3 would be higher than if the substrate were further removed. This is because GeH and SiH are shorter lived more highly reactive species than are GeH3 and SiH3. Therefore, in this manner, the thin film composition may be controlled.
In a microwave deposition apparatus useful for performing the method of the instant invention, a modified Linear Applicator is placed inside the vacuum environment and a modified single point microwave vacuum feed-through is used to supply microwave energy to the applicator. In this way, the only vacuum window is the relatively small one in the microwave feed-through itself.
FIG. 2 is a schematic depiction of a microwave deposition system including the improved microwave vacuum feed-through 2 and improved linear applicator 1 useful in performing the method of the present invention. Microwaves (typically at a frequency of 2.54 GHz and a power of about 2-5 kWatts), are created in microwave generator 4. These microwaves travel along the microwave wave guide 3, passing through circulator 7. The circulator 7 prevents any reflected microwave energy from entering the microwave generator by passing the reflected energy to the dummy load 6. The microwave energy created in the generator 4 also passes through a microwave power meter 5, which measures the forward and reflected microwave power. Next the microwave energy passes through the improved microwave vacuum feed-through 2 which provides the vacuum-to-air seal at the deposition chamber wall 8. Finally the microwave energy passes into the improved linear applicator 1 of the present invention. As the microwave energy exits the applicator 1, some of the energy is reflected back into the applicator 1 by reflectors 9 and is reradiated at other points along the applicator.
Microwave energy which exits the applicator 1, interacts with the static magnetic filed which is created by magnets 21 (permanent magnets and/or electromagnets) creating an electron cyclotron resonance condition within the plasma which is contained between the applicator 1 and the substrate 24. The additional non-microwave electronic energy is provided to the plasma via low frequency antennae (also called electrodes herein) 23. Typically these antennae 23 are large diameter copper coils of about 3-5 loops. These antennae 23 are electrically attached to a low frequency alternating electrical field generator 22. The low frequency alternating electromagnetic energy emanating form the antennae 23, in conjunction with the magnetic field created by the magnets 21, causes an ion cyclotron resonance condition within the plasma.
Turning now to FIGS. 3 and 4, there is depicted therein a top and side view of an improved linear applicator useful in an apparatus for performing the method of the instant invention, respectively. FIG. 3 specifically illustrates the reflector panels 9 and the curvature thereof. Also illustrated in FIG. 3 is the rectangular applicator wave guide body 10. The applicator is cooled, as needed, by passing cooling fluid through channels 17 which are attached to the applicator body 10 on the wider face thereof which is opposite that which includes the radiative slot (reference numeral 12 of FIG. 4). Covering the radiative slot 12 is a loose fitting quartz plate 11.
Normally, one would expect that since the applicator body wave guide 10 is inside the vacuum environment, plasma would be produced on the inside of the wave guide as microwave energy travels therein. However, it has been found that this is not necessarily so. The formation of the plasma has been found to depend on the pressure within the waveguide. If the pressure is sufficiently low (i.e., less than about 1 mTorr) magnetic confinement then becomes necessary to sustain a plasma. In the operation of the system of the present invention, the average pressure within the applicator body is about 1 mTorr. The microwaves travel up the wave guide body 10 of the linear applicator and radiate out the radiative slot 12 on one side of the guide into a region of slightly higher pressure nearer the gas feed manifold (not shown). A loose fitting quartz plate 11 separates the inside of the guide body 10 from the region of elevated pressure. This plate 11 is neither a structural element, nor a major vacuum component.
Returning now to FIGS. 3 and 4, the wave guide 10 is a standard 1.5�3.0 in. guide. A slot 12 is cut along the length of the guide in the z-direction (large dark arrows in FIG. 4) on one of the wider faces thereof (i.e., the 3 in. side). It should be noted that the width of the slot is uniform along the entire length thereof. With respect to FIG. 4, the microwaves enter the bottom of the Applicator wave guide 10 from the feed-through (reference numeral 2 of FIG. 2), and radiate out the slot 12. Excess microwave energy not radiated out the slot is (normally) transmitted to the top of the guide (where it also radiates). If the slot is wide enough, and/or the length of the slot is long enough, no energy remains at the top of the guide. It should also be noted that, without the reflector fins 9 and, because the slot 12 is of uniform width, the energy radiated out of the slot 12 decays exponentially from bottom to top thereof.
The exponentially decaying property occurs when there is only radiating energy, i.e., only outward going microwave energy. The installation of the reflecting panels 9 plays an important role in creating uniformity of the radiating microwave energy, because they introduce another term to the radiation picture. That is, a reflected, inward traveling component of microwave energy. These panels 9, are attached on each of the narrower sides 13 of the applicator body 10 and curvedly extend past the face containing the long slot 12 toward the plasma zone. The curved panels 9, are formed of a microwave reflecting material such as stainless steal or aluminum and reflect a portion of the outgoing microwave energy back into the applicator wave guide body 10. In the present configuration, the width of the slot 12 is such that after 15 inches of slot, about 50% of the energy is transmitted to the top of the guide. However, the wave nature of microwaves is shown dramatically when one of the panels 9 is slowly brought into place. It has been found that the energy transmitted out the top of the waveguide body 10 drops down to only 30% and that as the other panel 9 is then brought into place, the energy transmitted out the top drops to near 0%, with only about 5% reflected back out the bottom of the applicator body 10. In other words, the installation of the reflecting panels 9 has actually increased the amount of microwave energy which is radiated out of the radiative slot 12). Curvature of the panels 9 is important to achieve the desired level of tuning, but the panels 9 are not required to be touching the sides 13 of the wave guide body 10. It has been found that the same results are obtained even when there is a small gap between the guide body 10 and the reflecting panels 9. Also, the loose quartz plate 11 shown in FIG. 3 does not qualitatively change the microwave radiation uniformity.
It is clear from the above discussion that uniformity is an inherent aspect of the linear applicator of the present invention. If one location along the slot 12 radiates more strongly than neighboring positions, there is then correspondingly more radiation to be reflected and fed back into the wave guide body 10. This energy can then be redistributed to other locations along the applicator 1. Uniformity of deposition has been measured to +/-5% over a distance of 12 inches.
Turning now to FIG. 5, there is depicted therein a cross sectional side view of the improved microwave vacuum feed-through of the present invention. The prior art microwave feed-through was designed to withstand the high temperature problems of direct exposure to the plasma, and its transmission property was not then of concern. Direct use of the prior-art feed-through in the system of FIG. 2 showed that a large impedance mismatch existed between the feed-through 2, the wave guide 3 and the linear applicator 1. High power measurements showed that for 5 kW incident from the MW generator, 2 kW were reflected by the feed-through so that 3 kWatts (at the most) were being delivered into applicator. Low power bench top measurements confirmed that 40% of the incident power was reflected. Those same measurements showed that only about 35% of the incident power was successfully coupled into the applicator wave guide 10. The remaining 25% was lost to radiation and/or to resistive losses at the connection between the applicator 1 and the feed-through 2.
Therefore, the microwave vacuum feed-through of the instant invention has been constructed to use constructive and destructive interference (i.e. the wave nature of microwaves) to eliminate the reflected portion of the microwave energy by impedance matching the feed-through 2, to the wave guide 3 and the applicator 1. The microwave feed-through 2 includes a feed-through body 20 which is essentially a hollow cylindrical chamber, although, if needed, a cooling jacket can be used to eliminate any possible heating problems. Within the body 20, is three or more dielectric plates 14. In a preferred embodiment, the dielectric plates consist of three 4 in. OD alumina disks which are each separated by a particular distance. Each of the spacings between the disks is different from the others and the optimum spacing is determined empirically to tune the impedance of the feed-through 2. The middle disk is preferably twice as thick as the other two disks and serves as the point to which the vacuum seal is made by a Teflon o-ring 19. Therefore, the spaces between the middle disk 14 and the linear applicator connection means 16 are under vacuum while the spaces between the middle disk 14 and the wave guide connection means 15 are filled with air. It should be noted here that all the materials which are placed within the feed-through body 20 must be microwave compatible.
The connection means 15 and 16 are formed such that a microwave tight seal is formed between said means and the wave guide 3 and the applicator 1 respectively. The feed-through also includes Viton o-ring sealing means 18 to provide a vacuum seal, at the chamber wall 8, between the interior vacuum region and the exterior air region.
Low power bench top measurements showed that the feed-through 2 of the present invention coupled up to 95% of the incident energy from the outer wave guide 3 to the applicator wave guide 10, with no detectable reflection. High power measurements (<3 kW) into a dummy load (i.e., no plasma conditions) confirmed the low power results. The unaccounted 5% is most likely due to resistive losses on the inside of the feed-through. With the nearly perfect transmission, a "transparent connection" has been achieved between the wave guide transmission line 3 and the applicator wave guide 10.
As was stated hereinabove, there are two ways to resonantly couple energy into a plasma: (a) by high frequency radiation, which couples into the electrons; and (b) by low frequency radiation, which couples into the ions. When energy is pumped into the ions, their energy is very effectively transferred into the neutrals owing to their similarity in masses. Heating of the neutrals is desirable because it is the neutrals which overwhelmingly account for the deposition rate. It should be noted that because a relatively few ions must heat a large number of neutrals, efficiency requirements dictate the need to resonantly couple energy into the ions.
Modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practice otherwise than as specifically described.
|Citing Patent
|Filing date
|Publication date
|May 21, 1993
|Jul 11, 1995
|Loders Croklaan B.V.
|Bloom-inhibiting fat blends
|Sep 2, 1993
|Sep 26, 1995
|International Business Machines Corporation
|Plasma reactor for processing substrates
|Apr 17, 1995
|Sep 10, 1996
|Loders Croklaan B.V.
|Bloom-inhibiting fat blends
|Dec 15, 1994
|May 27, 1997
|Sony Corporation
|Multilayer resist pattern forming method
|Feb 23, 1994
|Dec 9, 1997
|Applied Materials, Inc.
|Chemical vapor deposition chamber
|Sep 15, 1995
|Dec 1, 1998
|Daihen Corporation
|Plasma processing apparatus for radiating microwave from rectangular waveguide through long slot to plasma chamber
|Sep 29, 1997
|Mar 16, 1999
|Applied Materials, Inc.
|Chemical vapor deposition chamber
|Oct 30, 1997
|May 11, 1999
|RF/VHF plasma diamond growth method and apparatus and materials produced therein
|Dec 2, 1998
|Apr 3, 2001
|Applied Materials, Inc.
|Anti-notch thinning heater
|Feb 11, 1999
|Oct 9, 2001
|Jds Uniphase Corporation
|Integrated optic modulators with high gain bandwidth product
|Sep 8, 2000
|Apr 15, 2003
|Matsushita Electric Industrial Co., Ltd.
|Semiconductor thin film, semiconductor device employing the same, methods for manufacturing the same and device for manufacturing a semiconductor thin film
|May 19, 2003
|Aug 10, 2004
|Avery N. Goldstein
|Integrated circuit trenched features and method of producing same
|Mar 19, 2002
|Aug 24, 2004
|Avery N. Goldstein
|Integrated circuit trenched features and method of producing same
|Sep 13, 1999
|Jan 25, 2005
|Qinetiq Limited
|Formation of a bridge in a micro-device
|Mar 6, 2003
|Jan 25, 2005
|Matsushita Electric Industrial Co., Ltd.
|Semiconductor thin film, semiconductor device employing the same, methods for manufacturing the same and device for manufacturing a semiconductor thin film
|Oct 14, 2003
|Jan 10, 2006
|Nanochip, Inc.
|Phase change media for high density data storage
|Mar 31, 2004
|Feb 28, 2006
|Samsung Electronics Co., Ltd.
|Methods for forming a thin film on an integrated circuit device by sequentially providing energies to activate the reactants
|Oct 8, 1999
|May 23, 2006
|Hitachi, Ltd.
|Plasma processing apparatus and a plasma processing method
|Feb 26, 2002
|May 30, 2006
|Stmicroelectronics Nv
|Opto-electronic component
|Dec 3, 2004
|Nov 27, 2007
|Nanochip, Inc.
|Methods for erasing bit cells in a high density data storage device
|Jul 8, 2005
|Dec 18, 2007
|Nanochip, Inc.
|Method for forming patterned media for a high density data storage device
|Dec 29, 2005
|Feb 26, 2008
|Nanochip, Inc.
|Atomic probes and media for high density data storage
|Jul 8, 2005
|May 6, 2008
|Nanochip, Inc.
|Method for forming a reinforced tip for a probe storage device
|Dec 3, 2004
|May 27, 2008
|Nanochip, Inc.
|Methods for writing and reading highly resolved domains for high density data storage
|Feb 2, 2007
|Jun 24, 2008
|Nanochip, Inc.
|Devices and methods of detecting movement between media and probe tip in a probe data storage system
|Apr 5, 2007
|Aug 19, 2008
|Nanochip, Inc.
|Memory having a layer with electrical conductivity anisotropy
|Jul 8, 2005
|Dec 9, 2008
|Nanochip, Inc.
|Patterned media for a high density data storage device
|Aug 23, 2007
|May 11, 2010
|Research In Motion Limited
|Multi-band antenna apparatus disposed on a three-dimensional substrate, and associated methodology, for a radio device
|Aug 22, 2006
|Jul 12, 2011
|Lam Research Corporation
|Method for plasma etching performance enhancement
|Sep 13, 2011
|Ovshinsky Innovation Llc
|Thin film deposition via charged particle-depleted plasma achieved by magnetic confinement
|Aug 12, 2010
|Nov 1, 2011
|Ovshinsky Innovation Llc
|Plasma deposition of amorphous semiconductors at microwave frequencies
|Jan 10, 2012
|Seagate Technology Llc
|Hybrid photovoltaic cell using amorphous silicon germanium absorbers with wide bandgap dopant layers and an up-converter
|Aug 12, 2010
|Jan 24, 2012
|Ovshinsky Innovation, Llc
|Plasma deposition of amorphous semiconductors at microwave frequencies
|Aug 12, 2010
|Jul 17, 2012
|Ovshinsky Innovation, Llc
|Plasma deposition of amorphous semiconductors at microwave frequencies
|May 19, 2003
|Feb 5, 2004
|Goldstein Avery N.
|Integrated circuit trenched features and method of producing same
|Jan 18, 2002
|Jul 29, 2004
|Thomas Beck
|Device for ceramic-type coating of a substrate
|Oct 14, 2003
|Jul 29, 2004
|Rust Thomas F
|Phase change media for high density data storage
|Feb 26, 2002
|Aug 12, 2004
|Peter Rieve
|Opto-electronic component
|Mar 31, 2004
|Feb 10, 2005
|Chang-Hyun Ko
|Methods for forming a thin film on an integrated circuit device by sequentially providing energies to activate the reactants
|Dec 3, 2004
|Oct 20, 2005
|Rust Thomas F
|Methods for erasing bit cells in a high density data storage device
|Dec 3, 2004
|Oct 20, 2005
|Rust Thomas F
|Systems for writing and reading highly resolved domains for high density data storage
|Feb 7, 2006
|Jul 20, 2006
|Kazue Takahashi
|Plasma processing apparatus and a plasma processing method
|Jul 8, 2005
|Jan 11, 2007
|Nanochip, Inc.
|Methods for forming high density data storage devices with read/write probes with hollow or reinforced tips
|Jul 8, 2005
|Jan 11, 2007
|Nanochip, Inc.
|Method for forming patterned media for a high density data storage device
|Aug 22, 2006
|Feb 1, 2007
|Lam Research Corporation
|Method for plasma etching performance enhancement
|Jul 26, 2007
|Jan 31, 2008
|Sanjai Sinha
|Methods and systems for manufacturing polycrystalline silicon and silicon-germanium solar cells
|Sep 2, 2008
|Jan 8, 2009
|Kazue Takahashi
|Plasma processing apparatus and a plasma processing method
|Aug 23, 2007
|Feb 26, 2009
|Research In Motion Limited
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|Aug 28, 2008
|Mar 4, 2010
|Seagate Technology Llc
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|Jul 29, 2010
|Lockheed Martin Corporation
|Apparatus and method for diamond film growth
|Oct 28, 2010
|Ovshinsky Stanford R
|Thin Film Deposition via Charged Particle-Depleted Plasma Achieved by Magnetic Confinement
|Mar 28, 2013
|Taiwan Semiconductor Manufacturing Co., Ltd.
|Method and system for forming chalcogenide semiconductor materials using sputtering and evaporation functions
|Apr 26, 2010
|Mar 21, 2012
|Thin film deposition via charged particle-depleted plasma achieved by magnetic confinement
|Aug 13, 1999
|Feb 24, 2000
|Goldstein Avery N
|Integrated circuit trenched features and method of producing same
|Apr 4, 2002
|Oct 17, 2002
|Axcelis Technologies Inc.
|Plasma source having supplemental energizer for ion enhancement
|Apr 4, 2002
|Dec 5, 2002
|Axcelis Tech Inc
|Plasma source having supplemental energizer for ion enhancement
|Jul 27, 2007
|Jan 31, 2008
|Senergen Devices, Inc.
|Methods and systems for manufacturing polycrystalline silicon and silicon-germanium solar cells
|Apr 26, 2010
|Oct 28, 2010
|Ovshinsky Innovation, Llc
|Thin film deposition via charged particle-depleted plasma achieved by magnetic confinement
|Apr 26, 2010
|Jan 20, 2011
|Ovshinsky Innovation, Llc
|Thin film deposition via charged particle-depleted plasma achieved by magnetic confinement
|U.S. Classification
|427/571, 427/575, 427/255.29, 427/598, 427/579, 427/250, 427/576
|International Classification
|Cooperative Classification
|European Classification
|Jul 9, 1993
Owner name: ENERGY CONVERSION DEVICES, INC.
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Owner name: BEKAERT ECD SOLAR SYSTEMS, LLC, MICHIGAN
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text:
Knapp's News 3/30/14
George Knapp shares some items that have recently caught his attention, including an article about the strange cattle mutilation mystery.
Author and filmmaker Rich Martini discussed his research into near-death experiences and the afterlife, as well as provided an update on his investigation into the disappearance of Amelia Earhart. Open Lines followed in the latter half of the show.
George Knapp shares some items that have recently caught his attention, including an article about the strange cattle mutilation mystery.
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A new dwarf planet called 2012 VP113 has been found at our solar system's edge. The newly discovered body, about 280 miles in size, is even more distant than the dwarf planet Sedna (pictured, artist's conception).
An astronomer has discovered a "Goldilocks zone" planet that is thought to be nearly the same size as Earth.
George Knapp shares a number of items that have recently caught his attention including an article about how one or more fragments of a rare meteorite possibly landed near St. Thomas, Ontario.
Using over 10,000 photos taken by the Lunar Reconnaissance Orbiter, NASA has created an amazing interactive map of the moon's North Pole.
NASA's Solar Dynamics Observatory (SDO) caught an intense solar flare as it erupted from the surface of the sun on Wednesday.
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A new study on the asteroid impact believed to have caused the mass extinction of the dinosaurs has revealed a potential additional layer of devastation from the catastrophic event.
NASA's Hubble Space Telescope has photographed a never-before-seen view of an asteroid breaking apart in deep space.
NASA's 2015 budget request from the Federal government provides insights into which realms of research the agency plans to focus on in coming years
A strange signal from the center of the Milky Way may be the first direct evidence of dark matter, the elusive substance said to make up 85% of all matter in the universe.
It's part airship, plane and helicopter, and measures over 300ft long—60ft longer than the biggest airliners!
NASA's Kepler mission has announced a stunning bounty of new planet discoveries-- 715 new planets that orbit 305 stars!
Futurist and AI developer Ray Kurzweil has predicted that robots/computers will surpass human intelligence in just 15 years.
George Knapp shares several news items that have recently caught his attention, including articles on the Viking apocalypse, DHS's quest for a national license-plate recognition database, tsunami "ghost" stories from Japan and the possibility of alien life inside of atoms.
The Shroud of Turin is pictured on the iPhone/iPad app, Shroud 2.0, which allows users to zoom in on any part of a high resolution digital scan of the revered cloth.
George Knapp shares a number of items that have recently caught his attention, including an article about how nuclear bombs could save Earth from asteroids.
The European Space Agency has turned to humanity's distant past in an effort to reinforce the heat shield of its Solar Orbiter
NASA has determined the origins of the mysterious 'Pinnacle Island' rock which seemed to suddenly appear in a photo taken by the Mars Opportunity Rover this past January.
NASA celebrated the start of the 2014 Winter Olympics by releasing some breathtaking satellite images of the venues created for the games in Sochi, Russia.
NASA's Curiosity rover captured a view of our planet from its location on the Red Planet. In the new image, the Earth can be seen as the brightest point of light in the Martian sky with our moon just below it.
A fresh impact crater on Mars has been photographed by NASA's Mars Reconnaissance Orbiter.
A fossil bed in China with a well-preserved set of dinosaurs and mammals frozen in death poses has long puzzled scientists.
George Knapp shares a number of items that have recently caught his attention including his I-Team report on the 50-year old Paul Fronczak mystery.
A weird-looking robot could save your life one day. Take NASA's RoboSimian, for instance. The strange four-legged robot, which looks like a cross between a spider and monkey, recently competed in the DARPA Robotics Challenge Trials.
NASA scientists are baffled by a piece of rock that has mysteriously appeared in front of the Mars Opportunity rover.
A star photographed by Hubble called SBW1 may be getting ready to go supernova.
For astronauts aboard the International Space Station, Christmas continued into 2014 as the Cygnus spacecraft arrived on Sunday morning and brought with it, amongst the 2,780 pounds of supplies aboard the ship, holiday gifts for the denizens of the ISS
An uncanny new NASA X-ray image dubbed the "Hand of God" shows a cloud of material being ejected from a star that exploded in a supernova.

subset: commoncrawl


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Tomato Pick-Me-Up
Yield: Makes about 5-1/2 cups.
Serve this in mugs as a beverage or in small chowder bowls, sprinkled with snipped parsley and lemon rind.
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- 1 quart homemade chicken broth
- 1 can (46 ounces) tomato juice
- 6 sprigs fresh basil, or 1/4 to 1/2 teaspoon dried
- 1 large bay leaf
- 3 sprigs fresh oregano, or 1/8 to 1/4 teaspoon dried
- Juice of 2 lemons
- 1/3 cup vermouth
Instructions:Hear broth, tomato juice, herbs, and lemon juice to boiling. Add vermouth and simmer until serving time. Remove bay leaf.
Updated Wednesday, December 12th, 2007


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I haven't done that yet.... Will get there. May have to buy some now .Mama Roneck said:
I think he said he boiled them for a minute on each side. Looks great!
I assume you topped them with smoked salmon from your egg?


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Say 'I do' at Conrad Maldives Rangali Island, your dream wedding destination offering a romantic beach setting or an elaborate underwater ceremony in Ithaa Undersea Restaurant.
- Conrad Maldives Rangali Island Hotel - Maldives Beach Wedding Underwater
- Get married on the beach. Conrad Maldives Rangali Island Hotel - Maldives Beach Wedding
- Conrad Maldives Rangali Island Hotel - Maldives Beach Wedding - Love Hammock
- Conrad Maldives Rangali Island Hotel - Maldives Beach Wedding - Band
An idyllic dreamscape, Conrad Maldives Rangali Island personifies bliss, a place to renew vows and celebrate love, pre-wedding photography and the perfect location to wake each morning to continue the extraordinary journey as husband and wife.
We have designed three renewals of love ceremonies inspired by you.
Beach Blessing
A quintessential Maldivian ceremony held on the white sands of Rangali Island overlooking the turquoise waters of the Indian Ocean.
Undersea Vows
For a truly unique experience, Ithaa Undersea Restaurant provides an extraordinary backdrop, situated five metres underwater and surrounded by the vibrant coral reef, your ceremony will be witnessed by the colourful ocean inhabitants. Ithaa is the world's only undersea water chapel.
Castaway Ceremony
Sail the crystal blue waters and rediscover love in enchanting surroundings. Castaway on the resorts traditional Turkish yacht Rangali Ranni for a truly memorable experience designed to be just as awe-inspiring as the moment you met.
Prosperity by Jereme Leung
Location: Ithaa for the ceremony, Ufaa for the reception dinner
Cost: 3,888++
Dinner: Ufaa by Jereme Leung - special auspicious menu designed by Jereme
Family, 8 guests +
All details as above however served for 8+ guests
Also for the group ceremony's include 'gate crashing' in one of the Sunset Water Villas - subject to availability
Escape the Ordinary. Experience the Extraordinary.
Photography Opportunities
The azure blue waters and white sandy beaches accented by lush tropical greenery provide the striking backdrop for exchanging vows and honeymoons. Whether you are on your honeymoon or scouting for locations prior to the big day, Conrad Maldives Rangali Island provides the perfect location and personalised service to ensure one of the most important occasions in your life is as inspired as you dreamt them to be.
Our Gift to You
Celebrate the anniversary of your vows with us and receive the following as our gift to you.
- Save 25% on our Best Available Rate
- Complimentary upgrade to the next Villa category
- Daily breakfast and dinner in Atoll Market
Terms and Conditions
Offer is subject to availability for stays booked between June 16, 2015 and December 31, 2016 and completed between July 16, 2015 and July 16, 2017. Advance reservations are required. Rates are valid for single/double occupancy and exclusive of all taxes, incidental charges, gratuities and resort fees where applicable. Stay a minimum four nights and save 25% on our Best Available Rate, complimentary upgrade to the next Villa category, daily buffet breakfast and dinner in Atoll Market. 25% discount off the Best Available Rate is not combinable with any other offers and specials Complimentary upgrade excludes Sunset Water Villa; complimentary upgrades are subject to availability. Reservations must be made direct with the resort, when booking, please request the "Anniversary Package" and ensure you quote your reservation details from your vow ceremony the year prior. Blackout dates (24 December - 9 January, 2016 and 1 - 15 February, 2016) apply additional restrictions apply.


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Chicken Enchiladas
Total Time
Prep 10 mins
Cook 15 mins
This is a quick and easy recipe that came from my friend Kathy. If you have cooked chicken this comes together quick and seems like you cooked all day.
Ingredients Nutrition
- 1 onion, chopped
- 2 garlic cloves, finely chopped
- 1 tablespoon oil
- 1 (4 ounce) can roasted green chilies
- 3 cups cooked chicken, shredded
- 1 (10 ounce) can mild enchilada sauce
- 2 cups jalapeno jack cheese, shredded
- 1 cup half-and-half
- 10 corn tortillas
- Saute onion and chopped garlic in oil in a large skillet, about 5 minute Add chopped green chilis, chicken and enchilada sauce. Cook 2 minute Stir in 1/2 cup of the shredded cheese and remove from heat.
- Coat a 13X9 pan with nonstick cooking spray.
- Microwave corn tortillas 6 at a time covered with a damp paper towel.
- Dip each tortilla in warm water then shake it off.
- Fill each with about 1/3 cup of the chicken mixture, roll up and place seam side down in the pan.
- Top with Half and Half and sprinkle with remaining pepper jack cheese.
- Bake at 375 degrees for 10 minute then broil 5 min or until golden.


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SUNDAYS 10:45 a.m., Café Milano, Houma Couche Couche 4 p.m., The Jolly Inn, Houma Renegade 8 p.m., P.J.'s Bayouside Lounge, Chauvin TUESDAYS 5:45 p.m., Café Milano, Houma Todd Adams 8 p.m., Aficionados, Houma WEDNESDAYS 5:45 p.m., Café Milano, Houma Gary
Published: Thursday, June 23, 2005 at 6:01 a.m.
Last Modified: Wednesday, June 22, 2005 at 11:00 p.m.
Reader comments posted to this article may be published in our print edition. All rights reserved. This copyrighted material may not be re-published without permission. Links are encouraged.
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Ben DangShared publicly -
Love this commercial. Great reasons why collaboration is key to innovate.
Add a comment...
AngularJS — Superheroic JavaScript MVW Framework
AngularJS is what HTML would have been, had it been designed for building web-apps. Declarative templates with data-binding, MVW, MVVM, MVC,
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Software Engineering for Software as a Service
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Algorithms, Part II
Algorithms, Part II is a free online class taught by Robert Sedgewick, Kevin Wayne of Princeton University
We are CrossFit enthusiasts - Join our Google+ community, share the CrossFit love.


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Get an insight into Valve Solutions digital platform and customised B2B digital marketing solutions we offer. We promote business verticals in Manufacturing, Industrial Automation, Process Automation. Valve Solutions has 10,000+ global professionals across our social media channels. 50,000+ unique visitors to our blog. We help SME's scale and reach global audience, markets and industry using the power of digital media at affordable prices. For more details visit our Linkedin company page www.linkedin.com/company/valve-solutions


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Bizarre way to make an argument. What do you think?
Author Archives: Gun Digest Editors
Savage Model 11 Scout Rifle Introduced
The Savage Model 11 Scout Rifle looks to be a versatile and accurate do-it-all rifle loaded with features.
Safety Warning and Recall Notice for IMR 4007SSC Powder
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Savage Arms B.MAG Bolt (17 WSM) Recall Notice
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Is Reloaded Carry Ammo a Good Idea?
Been thinking about using reloaded handgun ammo as your concealed carry choice? It's not as cut-and-dried and you might think.
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Reasons Why BLADE Show is the Summer's Can't Miss Event
Here's why you can't afford to miss BLADE Show 2015


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GreatNonprofits is the best way to find great local nonprofits.
Volunteers and donors use GreatNonprofits to search for ratings and reviews of nonprofits in their town.
Featured Review
Reel Grrls is such an innovative non-profit, teaching young people to create media that influences how we see the world- with a "feminist lens". I love that phrase and I believe that in our media flooded... more
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Saint Petersburg Children & Youth Nonprofits and CharitiesChildren & Youth X
Saddle Up Riding Club Inc
4.9 stars 65 reviews
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As an Air Force Veteran with a disability, I've been participating in the theraputic horse riding at Saddle Up Riding club for... more »
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- Redingtn Shor, FL
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R'Club Child Care, Inc.
4.5 stars 47 reviews
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Being a parent who has higher standards because I've performed in a childcare leadership role, I feel the 28th St site is the... more »
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4.8 stars 13 reviews
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I grew up in the extremely diverse city of Chicago, where I was lucky enough to meet and be friends with people from all kinds... more »
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Heart Gallery of Pinellas & Pasco
5 stars 7 reviews
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We adoptedOur 3 children From the heart gallery. They gave us the chance of having a family. Everyone Involved will always be... more »
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Alpha House of Pinellas County Inc
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please read what was written and not what you want to read....terribly run organization is very different than having to deal... more »
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Advantage Village Academy (AVA) is instrumental in providing a safe haven for many underprivileged youth in the Pinellas County... more »
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text:
Definition of upstart
intransitive verb
: to jump up (as to one's feet) suddenly
14th Century
First Known Use of upstart
14th century
Rhymes with upstart
apart, at heart, bar chart, blackheart, bogart, Bogart, by heart, clip art, crash cart, depart, Descartes, dispart, dogcart, Earhart, eye chart, false start, fine art, flowchart, folk art, forepart, Froissart, go-cart, golf cart, greenheart, handcart, head start, impart, in part, jump-start, junk art, kick-start, mouthpart, Mozart, outsmart, oxcart, oxheart, pie chart, pop art, pushcart, rampart, real part, redstart, restart, street-smart, Stuttgart, sweetheart, take heart, take part, tea cart, time chart, tipcart, tramp art, voice part
Simple Definition of upstart
: a person who has recently begun an activity, become successful, etc., and who does not show proper respect for older and more experienced people
: a newly successful person, business, etc.
Full Definition of upstart
1 : one that has risen suddenly (as from a low position to wealth or power) : parvenu; especially : one that claims more personal importance than is warranted
2 : a start-up enterprise
upstartplay \ˈəp-ˈ\ adjective
Examples of upstart in a sentence
a young upstart from Harvard who thinks he knows more than the boss
<having made their money in oil decades ago, they consider these billionaire dot-commers mere upstarts>
First Known Use of upstart
Other Business Terms
UPSTART Defined for Kids
Definition of upstart for Students
: a person who gains quick or unexpected success and shows off that success
Learn More about upstart
Thesaurus: All synonyms and antonyms for upstart Spanish Central: Translation of upstart Nglish: Translation of upstart for Spanish speakers Britannica English: Translation of upstart for Arabic speakers
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What made you want to look up upstart? Please tell us where you read or heard it (including the quote, if possible).


text:
Here come the Wimbledon WAGs! Tennis stars' girlfriends serve up some glamour
Coleen Rooney, Abbey Clancy and Victoria Beckham made the word WAG synonymous with football, glitz and glamour.
But now there's a new breed of WAG in town and they have landed in Wimbledon.
This year's pack of loyal wives and girlfriends will be supporting their athletic other halves in the Wimbledon Championships and there is no doubt that they will add a spot of glamour to the sideline.
Andy Murray's 23-year-old girlfriend Kim Sears is regularly seen cheering him on
The pair currently live together in his Surrey home
Andy Murray's girlfriend Kim Sears leads the pack.
The pair have been together since 2006 and at almost every big match she can always be seen, standing shoulder to shoulder with the other woman in Murray's life - his mother - cheering him from the stands.
The 23-year-old English Literature graduate and her tennis boyfriend share a £5million, six-bedroom home in Oxshott, Surrey, and she has been by his side for most of his career, despite a temporary split in 2009.
The world number four recently spoke warmly of his pretty blonde girlfriend - despite joking that she would never be able to force him up the aisle - and he spoke of his settled and happy life with her in an interview with David Frost.
Next up is fellow blonde, Brookyln Decker, another loyal WAG and avid supporter of husband Andy Roddick, who she married in 2009.
The 24-year-old model, who has appeared in the Sports Illustrated swimsuit issue, is a Texan native who caught Andy's eye while was skimming through a copy of U.S. magazine Sports Illustrated Swimwear Edition in 2006.
Andy spotted his model wife Brooklyn Decker in a copy of Sports Illustrated
He asked his agent to contact Brooklyn and ask her for a date and the couple have been inseparable since, tying the knot in April last year at their home in Austin, Texas.
Brooklyn was first discovered in a North Carolina shopping mall when she was a teenager.
She went on to become a household name when she appeared in Sports Illustrated Swimsuit Edition in 2006, and then graced the cover last year.
Brooklyn Decker gives her husband the thumbs-up following his victory
She featured alongside Jennifer Aniston in the hit romantic comedy Just Go With it, playing Palmer Dodge, the much younger love interest of the film's main character played by Adam Sandler.
This year Brooklyn starred in What to Expect When You're Expecting alongside Cameron Diaz and Jennifer Lopez.
Another tennis WAG who commands a great deal of television attention when cheering her partner on court-side is Novak Djokovic's beautiful girlfriend Jelena Ristic.
The pair have been dating for around five years and luckily finance graduate Jelena is reportedly a big tennis fan, enjoying both playing and watching.
Jelena watches on as boyfriend Novak Djokovic plays at day one of the Championships Wimbledon 2012
The Serbian star is known for treating his 24-year-old girlfriend to weekend breaks.
The champion revealed last week that he and Jelena spent a couple of days in Gleneagles, close to Murray's home town of Dunblane, and even sent him a picture as a memento.
Jelena cheers her partner on, rain or shine
Rafael Nadal, the world number two, may have a third Wimbledon title firmly in his sights but he can't keep his eyes off his stunning childhood sweetheart, Maria Perello.
Miss Perello, 23, and Nadal, 26, grew up in the same village, Manacor, on the holiday island of Mallorca.
Rafael Nadal and Maria Perello grew up together in Spain
Maria, who is affectionately called Xisca by friends and family and described as an 'intelligent girl from a good family', studied business in Mallorca.
Speaking about their relationship recently, friend Pedro Hernadez said: 'Raf and Xisca are both very shy and ordinary people who like to live simply.
'They are not at all interested in a celebrity lifestyle. They get together when the tournaments are over. That's how Raf winds down.'
Maria is part of the family as she cheers Nadal on with his sister Maria Isabel Nadal
And Xisca's family insist she has no interest in becoming a tennis WAG because of her relationship with Nadal.
Her cousin said of her: 'She is a straightforward, no-nonsense girl not interested in glamour and fame.
'You won't see her rolling out of a nightclub or laden down with designer bags after a shopping spree.'
The couple are clearly very comfortable in each others company and were spotted strolling together on the eve of Wimbledon.
Rafael Nadal looked relaxed whilst out with his girlfriend Maria Perello on the eve of Wimbledon 2012
Miss Perello prepared for the elements in a stylish beige three-quarter mac, patterned scarf and boots, as her tanned tennis star boyfriend draped an arm over her shoulder and tightly clasped her hand.
And finally there is Roger Federer and his wife of three years, Mirka, who are said to be extremely committed to one another.
The 28-year-old tennis ace married Mirka in an intimate ceremony in his home town of Basel, Switzerland in 2009.
Mirka, 34, is a former WTA tennis player and the couple met in 2000 when they were both competing at tennis for Switzerland in the Sydney Olympics.
Mirka and Roger have a solid and stable relationship, they married in 2009
Born in Slovakia, she emigrated to Switzerland with her family at the age of two. She was forced to retire early from the WTA Tour because of injury.
She instead became one of Federer's managers and soon his constant companion as he toured the world.
Their relationship is said to be one of the most enduring in the temptation-filled world of competitive sport and they have twins Charlene Riva and Myla Rose.
In an interview, Federer once said of Mirka: 'As long as I wake up in the morning and she is next to me, that's all that matters.'
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The search widget does not display password protected content (posts, specifically) in the results. I need it to!
I've tried the "Search Unleashed" plugin, and it didn't work for me. Neither did deactivating all other plugins, or the theme itself.
Removing the password protection made the posts searchable, but that's not an option for me. It does show it's the password protection that is the issue, though.
Any help? Thanks.