Process for making an imaged oxygen-reactive ion etch barrier

• US 4,464,460 A
• Filed: 06/28/1983
• Issued: 08/07/1984
• Est. Priority Date: 06/28/1983
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Miller, Robert D., Willson, Carlton G., Hiraoka, Hiroyuki, Hofer, Donald C., Pederson, Lester A.
• Primary Examiner(s): Kittle, John E.
• Assistant Examiner(s): Dees, Jose G.
• Application Number:
  US06/508,644
• Time in Patent Office: 406 Days
• Field of Search: 430/322, 430/323, 430/312, 430/313, 430/314, 430/317, 430/270, 430/271, 430/303, 430/272, 430/316, 156/643, 156/652, 156/657, 156/659.1, 156/661.1, 156/668, 427/38
• US Class Current: 430/323
• CPC Class Codes: G03F 7/0754 Non-macromolecular compounds containing silicon-to-silicon bonds G03F7/0752 takes precedence
• CPC Class Codes: G03F 7/094 Multilayer resist systems, e.g. planarising layers

Abstract

A process for making an image oxygen-reactive ion etch barrier using a polysilane that is resistant to resistive ion etching and is also a positive acting resist.

Claims

1. A process for making an imaged oxygen-reactive ion etch barrier, said process being characterized by the steps of

(1) coating a substrate with a polymer layer;

(2) dissolving a polysilane having a molecular weight (Mw) above 4,000 and a glass transition temperature above 100°

C. in an organic solvent in which said polymer layer is insoluble;

(3) coating said dissolved polysilane as a film on the polymer coated substrate;

(4) exposing said polysilane film in an imagewise manner to radiation;

(5) developing the polysilane film by contacting it with a solvent to dissolve the areas which have been exposed to radiation and thereby uncover portions of the polymer layer; and

(6) exposing the system to anisotropic oxygen-reactive ion etching to uncover portions of the substrate and thereby generate a high resolution, high aspect ratio relief structure.

3. A process as claimed in claim 1 wherein the polysilane is poly(phenyl methyl silane).

4. A process as claimed in claim 1 wherein the polysilane is a 1:

1 copolymer of dichlorodimethylsilane and dichlorophenylmethylsilane.

5. A process as claimed in claim 1 wherein the polysilane is poly(cyclohexyl methyl silane).

2. A process for making an images oxygen-reactive ion etch barrier, said process being characterized by the steps of:

(1) coating a substrate successively with first a polymer layer, secondly a layer of polysilane having a molecular weight (Mw) above 4,000 and a glass transition temperature above 100°

C. and cast from a solvent in which said polymer layer is insoluble, and thirdly with a lithographic resist layer;

(2) imagewise exposing and then developing the resist layer to form relief images that uncover portions of the polysilane layer;

(3) exposing the uncovered portions of the polysilane layer to CF₄ -O₂ etching and thereby uncovering portions of the polymer layer; and

(4) exposing the system to anisotropic oxygen reactive ion etching to uncover portions of the substrate, and thereby generate a high resolution, high aspect ratio relief structure.

6. A process as claimed in claim 2 wherein the polysilane is poly(phenyl methyl silane).

7. A process as claimed in claim 2 wherein the polysilane is a 1:

1 copolymer of dichlorodimethylsilane and dichlorophenylmethylsilane.

8. A process as claimed in claim 2 wherein the polysilane is poly(cyclohexyl methyl silane).