US 10,474,032 B2  34  33  By increasing the polyvinyl alcohol loading from 0%  through 3% of total solids (0%-0.080% of solution), post  develop residue can be significantly decreased or eliminated,  as shown by scanning electron micrograph of the processed  wafer substrate.  EXAMPLE 37  EXAMPLE 35  Improved Coat Quality with Hydrolyzed PVA  Coating Composition Comprising Modified Silica  A further coating composition of the inventions was  prepared by admixing the following components in the  following amounts based on total composition weight:  0.053 weight % Poly(vinyl alcohol), Variable degree of  hydrolysis  0.080 weight % Perfluorobutane sulfonic acid  0.027 weight % Dodecyl benzene sulfonic acid  0.080 weight% Surfynol-104  2.650 weight % Colloidal silica, <20 nm  2.000 weight% 1-Propanol  95.110 weight% Water  The above solution was spin coated onto an unprimed  silicon wafer substrate.  It was found by scanning electron  micrograph analysis that Increasing the degree of hydrolysis  of polyvinyl alcohol improved the applied coating quality, in  particular a more uniform coating was provided.  6 nm colloidal silica stabilized with ammonium hydrox› ide (pH of7.3) ina 6.3 weight% solids solution in deionized  water was surface modified with various water soluble,  reactive silanes.  3-(trihydroxysilyl)-1-propane-sulfonic acid, as  shown  below, was used as the surface modifier.  Preparation:  100 grams of a 6.3 wt % colloidal silica solution was  mixed with 3-(trihydroxysilyl)-1-propane-sulfonic acid in  varying ratios. The resulting solutions were then heated to  30°  C. for 60 hours. Upon cooling the resulting solutions  were mixed with a 5 wt % poly( ethylene oxide) solution,  2000  Mn, in a 1: 1 volume ratio to check for compatibility.  The solutions were also coated on silicon substrates to check  film properties.  A further coating composition of the inventions was  prepared by admixing the following components in the  following amounts based on total composition weight:  0.013 weight % Poly(vinyl alcohol)  0.027 weight % Dodecyl benzene sulfonic acid  0.080 weight% Surfynol-104  2.650 weight% Colloidal silica, Sulfonic acid modified (23  wt% silane)  2.000 weight% 1-Propanol  95.230 weight % Water  The modified silica was prepared as described in Example  36 above. This composition solution was spin coated onto a  dried DUY photoresist layer that had been applied to an  HMDS primed silicon wafer substrate. The above stack was  then imaged on an ASML/300 DUY stepper. Following  exposure, the wafers were baked at 110°  C./60 sec. and then  developed for 45 seconds with 0.26N TMAH developer. The  resulting 400 nm  1:  1 line/space patterns were then screened  under SEM (Scanning Electron Micrograph). Improved  resolution of the patterned photoresist image was seen with  use of this overcoating composition relative to a comparable  processed photoresist that did not include use of the over- coating composition.  EXAMPLE 38  Preparation of Additional Surface Modified Silica  6 nm colloidal silica stabilized with ammonium hydrox› ide (pH of 7.3) as 6.3% solids solution in deionized water  was surface modified with various water soluble, reactive  silanes.  Methoxy-poly( ethylene oxide )-tri(methoxy)silane, 525  Mw, as shown below, was used as the surface modifier.  Preparation:  100 grams of a 6.3 wt % colloidal silica solution was  mixed with the above silane in various ratios. The resulting  solutions were then heated to 40°  C. for 60 hours. Upon  cooling the resulting solutions were mixed with a 5 wt %  poly( ethylene oxide) solution, 2000  Mn, in a 1: 1 volume  ratio to check for compatibility. The solutions were also  coated on silicon substrates to check film properties.  Silica 6.3%  Silica  Silane  Compati- solution  solids  solids  Silane  SiOH:Silane  bility  Sample  grams  grams  grams  wt%  molar ratio  witb PEO  A  100.00  6.300  3.250  34.0%  1.5  Yes  B  100.00  6.300  2.600  29.2%  1.9  Yes  C  100.00  6.300  1.950  23.6%  2.5  Yes  D  100.00  6.300  1.300  17.1%  3.7  No  E  100.00  6.300  0.650  9.4%  7.5  No  F  100.00  6.300  0.325  4.9%  15.0  No  G  100.00  6.300  0.163  2.5%  29.9  No  H  100.00  6.300  0.000  0.0%  00  No  Redispers- ibility  in Water  Yes  Yes  No  No  No  No  No  No  EXAMPLE 36  Preparation of Surface Modified Silica 