# US 4,397,940 A · Reducing the liquid solvent development time of a polymeric relief image

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 4,397,940 A
- Document ID: US4397940A
- Status: Granted
- Kind: A
- Application number: 06/392,647
- Filed: 1982-06-28
- Granted: 1983-08-09
- Earliest claimed: 1982-06-28
- Assignees: Armstrong World Industries, Inc.
- Inventors: Jerome D. Wisnosky; Doris F. Carlson
- Web page: https://patentgrep.com/patent/US4397940A

## CPC

- G03F 7/30: Imagewise removal using liquid means
- G03F: PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR; (phototypographic composing devices B41B; photosensitive materials or processes for photographic purposes G03C; electrophotography, sensitive layers or processes therefor G03G)

## Abstract

The present invention contemplates a method to reduce the liquid solvent contact time required to develop a latent polymeric relief image in a layer of polymeric material that is selectively exposed to radiation so that there is formed a layer having exposed and unexposed areas. In the method of the present invention, the layer is exposed to the gaseous vapors of at least one solvent for the more soluble area, after which it is contacted with a liquid solvent which preferentially dissolves the material from the more soluble area and which does not affect the polymerized material which forms the relief image.

## Claims

### Claim 1

A method for forming a polymeric relief image in a layer that comprises areas of soluble and insoluble material, which method comprises:
(a) exposing the layer to the vapors of at least one solvent for the soluble material; and
(b) contacting the vapor exposed layer with a liquid solvent which preferentially dissolves the soluble material and which does not affect the insoluble material to thereby form a polymeric relief image.

### Claim 2 (depends on 1)

The method of claim 1 wherein, in step (b), the liquid solvent is sprayed onto the layer.

### Claim 3 (depends on 1)

The method of claim 1 wherein the material is differentially solubilized by an image-wise exposure to radiant energy through a mask.

### Claim 4 (depends on 3)

The method of claim 3 in which the material is a negative photoresist.

### Claim 5 (depends on 3)

The method of claim 3 in which the material is a positive photoresist.

### Claim 6

An apparatus for forming a polymeric relief image in a layer that comprises areas of soluble and insoluble material, which apparatus comprises:
(a) means for exposing the layer to the vapors of at least one solvent for the soluble material; and
(b) means for contacting the vapor exposed layer with a liquid solvent which preferentially dissolves the soluble material and which does not affect the insoluble material to thereby form a polymeric relief image.

### Claim 7 (depends on 6)

The apparatus of claim 6 wherein the means for contacting the vapor exposed layer with a liquid solvent is a liquid solvent spray means.

### Claim 8 (depends on 6)

The apparatus of claim 6 wherein the material is differentially solubilized by an image-wise exposure to radiant energy through a mask.

### Claim 9 (depends on 8)

The apparatus of claim 8 in which the material is a negative photoresist.

### Claim 10 (depends on 8)

The apparatus of claim 8 in which the material is a positive photoresist.