US 9,551,933 B2  252  251  ing surfactants can be used. Examples of the fluorine› containing and/or silicon-containing surfactants include sur› factants described in JP-A-62-36663, JP-A-61-226746,  JP-A-61-226745, JP-A-62-170950, JP-A-63-34540, JP-A- 7-230165, JP-A-8-62834, JP-A-9-54432, JP-A-9-5988 and  U.S. Pat. Nos. 5,405,720, 5,360,692, 5,529,881, 5,296,330,  5,436,098, 5,576,143, 5,294,511 and 5,824,451. A nonionic  surfactant is preferred. The nonionic surfactant is not par› ticularly limited, but use of a fluorine-containing surfactant  or a silicon-containing surfactant is more preferred.  The amount of the surfactant used is usually from 0.001  to 5 mass %, preferably from 0.005 to 2 mass %, more  preferably from 0.01 to 0.5 mass %, based on the total  amount of the developer.  Also, the organic developer may contain an appropriate  amount of a basic compound, if desired. Examples of the  basic compound include those described above in the para› graph of [ 6] Basic Compound.  In the pattern forming method of the present invention, a  step of performing development by using an organic sol› vent-containing developer ( organic solvent development  step) and a step of performing development by using an  aqueous alkali solution ( alkali development step) may be  used in combination. Thanks to this combination, a finer  pattern can be formed.  In the present invention, the portion of low exposure  intensity is removed in the organic solvent development  step, and by further performing the alkali development step,  the portion of high exposure intensity is also removed. By  virtue of the multiple development process of performing  development a plurality of times in this way, a pattern can  be formed by keeping only the region of intermediate  exposure intensity from being dissolved, so that a finer  pattern than usual can be formed (the same mechanism as in  [0077] of JP-A-2008-292975).  In the pattern forming method of the present invention,  the order of the alkali development step and the organic  solvent development step is not particularly limited, but the  alkali development is preferably performed before the  organic solvent development step.  As regards the developing method, for example, a method  of dipping the substrate in a bath filled with the developer for  a fixed time ( dipping method), a method of raising the  developer on the substrate surface by the effect of a surface  tension and keeping it still for a fixed time, thereby per› forming the development (puddling method), a method of  spraying the developer on the substrate surface (spraying  method), and a method of continuously ejecting the devel› oper on the substrate spinning at a constant speed while  scanning a developer ejecting nozzle at a constant rate  ( dynamic dispense method) may be applied.  In the case where the above-described various developing  methods include a step of ejecting the developer toward the  resist film from a development nozzle of a developing  apparatus, the ejection pressure of the developer ejected (the  flow velocity per unit area of the developer ejected) is  preferably 2 mL/sec/mm 2  or less, more preferably 1.5  mL/sec/mm 2  or less, still more preferably 1 mL/sec/mm 2  or  less. The flow velocity has no particular lower limit but in 60  view of throughput, is preferably 0.2 mL/sec/mm 2  or more.  By setting the ejection pressure of the ejected developer  to the range above, pattern defects attributable to the resist  scum after development can be greatly reduced.  Details of this mechanism are not clearly known, but it is  considered that thanks to the ejection pressure in the above› described range, the pressure imposed on the resist film by  The percentage water content in the rinsing solution is  preferably 10 mass  %  or less, more preferably 5 mass  %  or  less, still more preferably 3 mass % or less. By setting the  percentage water content to 10 mass % or less, good  development characteristics can be obtained.  A plurality of these components may be mixed, or the  solvent may be used by mixing it with an organic solvent  other than those described above.  The monohydric alcohol used in the rinsing step includes  a linear, branched or cyclic monohydric alcohol, and specific  examples of the monohydric alcohol which can be used  include 1-butanol, 2-butanol, 3-methyl-1-butanol, tert-butyl  alcohol, 1-pentanol, 2-pentanol, 1-hexanol, 4-methyl-2-pen› tanol,  1-heptanol, 1-octanol, 2-hexanol, cyclopentanol,  2-heptanol, 2-octanol, 3-hexanol, 3-heptanol, 3-octanol and  4-octanol. As for the particularly preferred monohydric  alcohol having a carbon number of 5 or more, 1-hexanol,  2-hexanol, 4-methyl-2-pentanol, 1-pentanol, 3-methyl-1-bu› tanol and the like can be used.  After the step of performing development by using an  organic solvent-containing developer, more preferably, a  step of rinsing the film by using a rinsing solution containing  at least one kind of an organic solvent selected from the  group consisting of a ketone-based solvent, an ester-based  solvent, an alcohol-based solvent and an amide-based sol› vent is preformed; still more preferably, a step of rinsing the  film by using a rinsing solution containing an alcohol-based  solvent or an ester-based solvent is performed; yet still more  preferably, a step of rinsing the film by using a rinsing  solution containing a monohydric alcohol is performed; and  most preferably, a step of rinsing the film by using a rinsing  solution containing a monohydric alcohol having a carbon  number of 5 or more is performed.  Specific examples of the hydrocarbon-based solvent,  ketone-based solvent, ester-based solvent, alcohol-based  solvent, amide-based solvent and ether-based solvent are the  same as those described above for the organic solvent› containing developer.  The rinsing solution used in the rinsing step after the step  of performing development by using an organic solvent› containing developer is not particularly limited as long as it  does not dissolve the resist pattern, and a solution containing  a general organic solvent may be used. As the rinsing  solution, a rinsing solution containing at least one kind of an  organic solvent selected from the group consisting of a  hydrocarbon-based solvent, a ketone-based solvent, an ester› based solvent, an alcohol-based solvent, an amide-based  solvent and an ether-based solvent is preferably used.  The pattern forming method may include a step of rinsing  the film with a rinsing solution after the step of performing  development by using an organic solvent-containing devel› oper, but in view of, for example, throughput (productivity)  and the amount of rinsing solution used, it is preferred not  to include a step of rinsing the film with a rinsing solution.  After the step of performing development by using an  organic solvent-containing developer, a step of stopping the  development by replacing the solvent with another solvent  may be practiced.  Examples of the method for adjusting the ejection pres› sure of the developer include a method of adjusting the  ejection pressure by a pump or the like, and a method of  supplying the developer from a pressurized tank and adjust- ing the pressure to change the ejection pressure.  Here, the ejection pressure (mL/sec/mm 2 )  of the devel› oper is a value at the outlet of a development nozzle in a  developing apparatus.  the developer becomes small and the resist film or resist  pattern is kept from inadvertent chipping or collapse. 