Acid-strippable silicon-containing antireflective coating
A silicon-containing antireflective coating formulation comprising: (i) an aqueous base insoluble organosilicon component having a multiplicity of hydrocarbon groups derivatized with hydroxy groups in the absence of Si—O—C and Si—O—H moieties; (ii) a vinylether component having a multiplicity of vinylether groups; and (iii) a casting solvent. Also disclosed is a method for converting the silicon-containing antireflective coating formulation into a crosslinked silicon-containing antireflective film comprising organosilicon units interconnected by acetal or ketal groups. The method entails (a) coating a substrate with the silicon-containing antireflective coating formulation and (b) heating the coated substrate to a temperature at which crosslinking between the organosilicon silicon component and vinylether component occurs. Further disclosed is a method for patterning an antireflective coating on a substrate using the crosslinked silicon-containing antireflective film in a lithographic patterning process wherein the crosslinked silicon-containing antireflective film is situated between the substrate and a photoresist.
1. A layered structure comprising a substrate layer, a photoresist layer, and a crosslinked silicon-containing antireflective film between said substrate layer and photoresist layer, said crosslinked silicon-containing antireflective film comprising aqueous insoluble silsesquioxane units interconnected by acetal or ketal groups, wherein said silsesquioxane units and acetal or ketal groups are interconnected by bicycloalkyl or tricycloalkyl linking groups.
2. The antireflective film of claim 1 , wherein said antireflective film has a thickness of up to 100 nm.
3. The method of claim 1 , wherein said bicycloalkyl or tricycloalkyl linking groups comprise norbornyl groups.
4. A method for producing a crosslinked silicon-containing antireflective coating on a substrate, the method comprising:
(a) coating a substrate with a silicon-containing antireflective coating formulation comprising:
(i) an aqueous base insoluble silsesquioxane component having a multiplicity of bicycloalkyl or tricycloalkyl hydrocarbon groups derivatized with hydroxy groups in the absence of Si—O—C and Si—O—H moieties;
(ii) a vinylether component having a multiplicity of vinylether groups; and
(iii) a casting solvent; and
(b) heating the coated substrate at a temperature of at least 200° C. and up to 300° C. to effect crosslinking between the silsesquioxane component and vinylether component to result in a crosslinked silicon-containing antireflective coating comprised of aqueous base insoluble silsesquioxane units interconnected by acetal or ketal groups.
5. The method of claim 4 , wherein said silicon-containing antireflective coating formulation further comprises a thermal acid generator.
6. The method of claim 4 , wherein said vinylether component has the formula:
wherein v is an integer from 2 to 12 and w is an integer from 3 to 6.
7. The method of claim 4 , wherein said vinylether component has the formula:
wherein u is an integer of 3 to 12.
8. The method of claim 4 , wherein said temperature is at least 210° C. and up to 300° C.
9. The method of claim 4 , wherein said silicon-containing antireflective coating formulation further comprises an activatable acid generator.
10. The method of claim 9 , wherein said activatable acid generator is a thermal acid generator.
11. The method of claim 4 , further comprising overlaying said crosslinked silicon-containing antireflective coating with a layer of photoresist.
12. The method of claim 4 , wherein said bicycloalkyl or tricycloalkyl hydrocarbon groups comprise norbornyl groups.