# US 4,119,688 A · Electro-lithography method

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

- Number: US 4,119,688 A
- Document ID: US4119688A
- Status: Granted
- Kind: A
- Application number: 05/807,601
- Filed: 1977-06-17
- Granted: 1978-10-10
- Earliest claimed: 1975-11-03
- Assignees: International Business Machines Corporation
- Inventors: Hiroyuki Hiraoka
- Web page: https://patentgrep.com/patent/US4119688A

## CPC

- H01J 37/3175: {Projection methods, i.e. transfer substantially complete pattern to substrate}
- B82Y 10/00: Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
- B82Y 40/00: Manufacture or treatment of nanostructures
- G03F 1/20: Masks or mask blanks for imaging by charged particle beam [CPB] radiation, e.g. by electron beam; Preparation thereof
- G03F 1/50: Mask blanks not covered by G03F1/20 - G03F1/34; Preparation thereof
- H10P 76/2045: {Electron beam lithography processes}
- H01J 2237/31781: from patterned cold cathode
- Y10T 29/49156: with selective destruction of conductive paths
- H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H)
- B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- 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)
- H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

An electro-lithography method suitable for forming a high resolution pattern in an electron sensitive resist material is disclosed. This technology permits the inexpensive high resolution reproduction of masks for use in integrated circuits and magnetic bubbles. The method involves the application of a pulsed, electric field to two parallel electrodes having an electron beam resist layer positioned on one of the electrodes and a mask positioned between the second electrode and the resist layer. The mask forms a gap having a thickness of 10.sup.-4 m to 10.sup.-5 m with the resist layer.

## Claims

### Claim 1

An electro-lithographic method adapted to form a pattern of high resolution in an electron sensitive resist material comprising the steps of:
applying a layer of E-beam resist onto an anode,
placing a platelike opaque cathode parallel to said anode and facing said layer of resist to form a first gap therebetween,
placing a mask in said first gap between said cathode and said resist layer to form a second gap having a thickness of 10.sup.-4 m to 10.sup.-5 m between said mask and said resist layer,
regulating the pressure to 10.sup.-3 to 10.sup.-7 torr between said electrodes by pump means to provide an environment suitable for the formation of secondary electrons, and
applying a pulsed electric field of at least 2 KV to said cathode whereby secondary electrons from said cathode pass through the mask and are collimated to form a high resolution mask image in said resist layer.

### Claim 2 (depends on 1)

A method as described in claim 1 whereby the mask is placed to form said second gap having a thickness of 5.times.10.sup.-5 m to 2.times.10.sup.-5 m.

### Claim 3 (depends on 1)

A method as described in claim 1 whereby said mask is self sustaining and is placed on spacing means positioned on said resist layer to form said second gap between said resist layer and said mask and a third gap between said cathode and said mask.

### Claim 4 (depends on 1)

A method as described in claim 1 whereby said mask is placed on said cathode.

### Claim 5 (depends on 1)

A method as described in claim 1 whereby said E-beam resist is applied until the layer is between 1000 and 10,000 A.degree. thick.

### Claim 6 (depends on 1)

A method as described in claim 1 whereby the pressure is in the range of 10.sup.-3 to 10.sup.-5 Torr.

### Claim 7 (depends on 1)

A method as described in claim 1 including the step of placing a substrate layer between the anode and E-beam resist layer.

### Claim 8 (depends on 1)

A method as described in claim 1 including the step of applying a magnetic field perpendicular to the plane of said first gap.