Bilevel resist

• US 4,481,049 A
• Filed: 03/02/1984
• Issued: 11/06/1984
• Est. Priority Date: 03/02/1984
• Status: Expired due to Term

• Current Assignee: Bell Telephone Laboratories, Inc. (Nokia Corporation)
• Original Assignee: AT&T, Inc.
• Inventors: Reichmanis, Elsa, Smolinsky, Gerald
• Primary Examiner(s): Powell, William A.
• Application Number:
  US06/585,850
• Time in Patent Office: 249 Days
• Field of Search: 156/643, 156/646, 156/652, 156/655, 156/659.1, 156/661.1, 156/668, 156/904, 204/164, 204/192 E, 427/39, 427/41, 427/43.1, 427/54.1, 430/312, 430/313, 430/314-319, 430/329
• US Class Current: 438/725
• CPC Class Codes: G03F 7/0758 with silicon- containing groups in the side chains
• CPC Class Codes: G03F 7/094 Multilayer resist systems, e.g. planarising layers
• CPC Class Codes: Y10S 438/948 Radiation resist

Abstract

Excellent resolution in the lithographic fabrication of electronic devices is achieved with a specific bilevel resist. This bilevel resist includes an underlying layer formed with a conventional material such as a novolac resin baked at 200° C. for 30 minutes and an overlying layer including a silicon containing material such as a silicon derivative of poly(methyl methacrylate). This bilevel resist has the attributes of a trilevel resist and requires significantly less processing.

Claims

1. A process for fabricating a device comprising the steps of

forming a radiation sensitive region, on a substrate, patterning at least a portion of said region, and

further processing said substrate characterized in that

said region comprises a composition formed by a polymerization process employing a material represented by the formula ##STR8## where R'"'"' contains silicon and is chosen so that the T_g of said composition is higher than 50°

C., and the silicon weight percentage of said composition is at least 6 percent.

2. The process of claim 1 wherein R is represented by the formula ##STR9## where X, Y, and Z are chosen so that the T_g of said composition is higher than 50°

C., and the silicon weight percentage of said composition is at least 6 percent.

3. The process of claim 2 wherein said R is chosen from the group consisting of trimethylsilylmethyl, 2-(trimethylsilyl)ethyl, 3-(trimethylsilyl)propyl, trimethoxysilylmethyl, 2-(trimethoxysilyl)ethyl, 3-(trimethoxysilyl)propyl, 3-(pentamethyldisiloxy)propyl, 3-[bis(trimethylsiloxy)methylsilyl]propyl, and 3-[tris(trimethylsiloxy)silyl]propyl.

4. The process of claim 1 wherein said composition is formed by a polymerization process employing said material and a monomer chosen from the group consisting of oxime and indanone compounds.

5. The process of claim 2 wherein said composition is formed by a polymerization process employing said material and a monomer chosen from the group consisting of oxime and indanone compounds.

6. The process of claim 1 wherein a region capable of selective removal is interposed between said radiation sensitive region and said substrate.

7. The process of claim 6 wherein said R is chosen from the group consisting of trimethylsilylmethyl, 2-(trimethylsilyl)ethyl, 3-(trimethylsilyl)propyl, trimethoxysilylmethyl, 2-(trimethoxysilyl)ethyl, 3-(trimethoxysilyl)propyl, 3-(pentamethyldisiloxy)propyl, 3-[bis(trimethylsiloxy)methylsilyl]propyl, and 3-[tris(trimethylsiloxy)silyl]propyl.

8. The process of claim 7 wherein said composition is formed by a polymerization process employing said material and a monomer chosen from the group consisting of oxime and indanone compounds.

9. The process of claim 6 wherein said composition is formed by a polymerization process employing said material and a monomer chosen from the group consisting of oxime and indanone compounds.

10. The process of claim 6 wherein said patterning comprises the step of subjecting said region to said radiation and then subjecting said region to a plasma discharge.

11. The process of claim 10 wherein said region capable of selective removal undergoes said removal by being subjected to a solvent.

12. The process of claim 10 wherein said plasma discharge comprises an oxygen plasma discharge.