Pattern-forming material and its production and use

Claim 2

A high-energy radiation-sensitive, pattern-forming resist material which consists of polysilsesquioxane having no hydroxyl groups in its molecule.

Claim 3

A pattern-forming material as in claim 1 in which the polysilsesquioxane has the formula: in which R 1 and R 2 may be the same or different and each represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted vinyl group, and m is an integer of from 25 to 4,000.

Claim 4

A pattern-forming material as in claim 2 in which the polysilsesquioxaneis a silylated polysilsesquioxane, of the formula: in which R 1 , R2 and m are as defined in claim 2.

Claim 5

A process for the production of a high-energy radiation-sensitive pattern-forming resist material, which comprises condensing a trifunctional siloxane and removing the active hydrogen atom of the remaining unreacted hydroxyl groups in the molecule of the resulting condensate, thereby forming polysilsesquioxane having no hydroxyl group in its molecule.

Claim 6

A process for the production of a high-energy radiation-sensitive pattern-forming resist material, which comprises condensing a trifunctional siloxane and removing the active hydrogen atom of the remaining unreacted hydroxyl groups in the molecule of the resulting condensate, thereby forming polysilsesquioxane having no hydroxyl group in its molecule.

Claim 7

A production process as in claim 4, in which the resulting condensate is silylated to remove the active hydrogen therefrom.

Claim 8

A production process as in claim 5, in which silylation is carried out by using monohalogenated silane as silylating agent.

Claim 9

A production process as in any one of claims 4 to 6, in which the polysilsesquioxane has the formula: in which R 1 and R 2 may be the same or different and each represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted vinyl group, and m is an integer of from 25 to 4,000.

Claim 10

A production process as in claim 7 in which the polysilsesquioxaneis asilylated polysilsesquioxane of the formula: in which R 1 , R 2 and m are as defined above.

Claim 11

A process for the formation of a resist pattern on a substrate, which comprises the steps of: coating on the substrate a solution of a resist material which is a resist material as claimed in any one of claims 1 to 3; drying the coated resist material in an inert gas; exposing the dried coating of the resist material to a desired pattern of high-energy radiation for patterning, and developing the patterned coating of the resist material.

Claim 12

A pattern formation process as in claim 9, which further comprises dry etching the underlying substrate through a pattern-wise developed coating of the resist material which acts as a mask.

Claim 13

A process for the formation of a resist pattern on a substrate, which comprises the steps of: coating on the substrate a solution of a lower layer-forming first resist material which consists of an organic resin; drying the coated first resist material in an inert gas; further coating on the dried coating of the first resist material a solution of an upper layer-forming second resist material which is a resist material as claimed in any one of claims 1 to 3; drying the overcoated second resist material in an inert gas; exposing the dried coating of the second resist material to a desired pattern of high-energy radiation for patterning; developing the patterned coating of the second resist material; dry etching the underlaying coating of the first resist material through a pattern-wise developed coating of the second resist material which acts as a mask, thereby transferring a pattern of the second resist coating to the underlying first resist coating.

Claim 14

A pattern formation process as in claim 11, in which the lower resist layer-forming organic resin is phenol resin, polyimide resin, or polystyrene resin.

Claim 15

A pattern formation process as claimed in claim 11 or 12, wherein the first resist layer has a thickness of from 1.5 to 3.0 µm and the second resist layer has a thickness of from 0.2 to 0.5µ.

Claim 16

A pattern formation process as in claim 11 or 12, which further comprises dry etching the underlying substrate through a pattern-wise etched coating of the first resist material which acts as a mask.

Claim 17

A process as claimed in claim 10 or 14, which is utilised in the production of semiconductor devices using a lithography process.