Process for forming mask pattern and process for producing thin film magnetic head

• US 6,187,513 B1
• Filed: 05/21/1999
• Issued: 02/13/2001
• Est. Priority Date: 05/29/1998
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Katakura, Toru
• Primary Examiner(s): Baxter, Janet
• Assistant Examiner(s): Walke, Amanda C.
• Application Number:
  US09/316,385
• Time in Patent Office: 634 Days
• Field of Search: 430/312, 430/394, 430/396, 430/319, 430/320, 430/325, 430/313, 360/113, 427/130, 427/131, 427/58, 427/264, 427/282
• US Class Current: 430/312
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 25/00 Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance
• CPC Class Codes: G03F 7/0035 Multiple processes, e.g. applying a further resist layer on an already in a previously step, processed pattern or textured surface
• CPC Class Codes: G03F 7/094 Multilayer resist systems, e.g. planarising layers
• CPC Class Codes: G11B 2005/3996 large or giant magnetoresistive effects [GMR], e.g. as generated in spin-valve [SV] devices
• CPC Class Codes: G11B 5/3163 Fabrication methods or processes specially adapted for a particular head structure, e.g. using base layers for electroplating, using functional layers for masking, using energy or particle beams for shaping the structure or modifying the properties of the basic layers
• CPC Class Codes: G11B 5/3967 Composite structural arrangements of transducers, e.g. inductive write and magnetoresistive read G11B5/3906 takes precedence

Abstract

It is to provide a process for forming a mask pattern and a process for producing a thin film magnetic head, in which burr is not formed on removing a resist.

The process for forming a mask pattern comprises a first coating step of coating a first resist on a surface, on which the mask pattern is formed; a first exposure step of forming a pattern latent image by exposing the first resist; a second coating step of coating a second resist on the first resist; a second exposure step of forming a pattern latent image by exposing the second resist; a first development step of forming an upper layer mask pattern by developing the second resist; and a second development step of forming a lower layer mask pattern by developing the first resist, the upper layer mask pattern having a resist bridge part, and a space being present between the resist bridge part and the surface, on which the mask pattern is formed.

Claims

1. A process for forming a mask pattern comprising

a first coating step of coating a first resist on a surface, on which said mask pattern is formed;

a first exposure step of forming a pattern latent image in said first resist by exposing the first resist;

a second coating step of coating a second resist on said first resist, in which said pattern latent image is formed in said first exposure step;

a second exposure step of forming a pattern latent image in said second resist by exposing said second resist;

a first development step of forming an upper layer mask pattern by developing said second resist, in which said latent image is formed in said second exposure step, with a first developer; and

a second development step of forming a lower layer mask pattern by developing said first resist, in which said latent image is formed in said first exposure step, with a second developer,

said upper layer mask pattern having a resist bridge part in a resist remaining part, in which said second resist remains, said bridge part bridging over a part of said lower mask pattern, in which said first resist is removed, and a space being present between said resist bridge part and said surface, on which said mask pattern is formed.

2. A process for forming a mask pattern as claimed in claim 1, wherein said first resist and said second resist are a positive resist.

3. A process for forming a mask pattern as claimed in claim 1, wherein said first resist and said second resist are an electron beam resist.

4. A process for forming a mask pattern as claimed in claim 1, wherein

in said first development step and said second development step,

said first developer is a developer having a solubility of said second resist in said developer is larger than a solubility of said first resist in said developer, and

said second developer is a developer having a solubility of said first resist in said developer is larger than a solubility of said second resist in said developer.

5. A process for forming a mask pattern as claimed in claim 1, wherein said resist remaining part in said upper layer mask pattern is larger than said resist remaining part in said lower layer mask pattern.

6. A process for producing a thin film magnetic head comprising

a thin film forming step of forming a thin film constituting said thin film magnetic head on a surface;

a mask pattern forming step of forming a mask pattern on said thin film formed in said thin film forming step; and

an etching step of shaping the thin film by removing said thin film that is exposed from said mask pattern formed in said mask pattern forming step by etching,

the mask pattern forming step comprising

a first coating step of coating a first resist on said thin film;

a first exposure step of forming a pattern latent image in said first resist by exposing said first resist;

a second coating step of coating a second resist on said first resist, in which said pattern latent image is formed in said first exposure step;

a second exposure step of forming a pattern latent image in said second resist by exposing said second resist;

a first development step of forming an upper layer mask pattern by developing said second resist, in which said latent image is formed in said second exposure step, with a first developer; and

a second development step of forming a lower layer mask pattern by developing said first resist, in which said latent image is formed in said first exposure step, with a second developer,

the upper layer mask pattern having a resist bridge part in a resist remaining part, in which said second resist remains, said bridge part bridging over a part of said lower mask pattern, in which said first resist is removed, and space being present between said resist bridge part and said surface, on which said mask pattern is formed.

7. A process for producing a thin film magnetic head as claimed in claim 6, wherein said first resist and said second resist are a positive resist.

8. A process for producing a thin film magnetic head as claimed in claim 6, wherein said first resist and said second resist are an electron beam resist.

9. A process for producing a thin film magnetic head as claimed in claim 6, wherein

in said first development step and said second development step,

said first developer is a developer having a solubility of said second resist in said developer is larger than a solubility of said first resist in said developer, and

said second developer is a developer having a solubility of said first resist in said developer is larger than a solubility of said second resist in said developer.

10. A process for producing a thin film magnetic head as claimed in claim 6, wherein said resist remaining part in said upper layer mask pattern is larger than said resist remaining part in said lower layer mask pattern.

11. A process for producing a thin film magnetic head as claimed in claim 6, wherein said thin film is a film having a magnetoresistance effect.

12. A process for producing a thin film magnetic head as claimed in claim 11, wherein said film having a magnetoresistance effect is a film formed by laminating plural thin film layers and has a giant magnetoresistance effect.

13. A process for producing a thin film magnetic head as claimed in claim 12, wherein said film having a giant magnetoresistance effect is a spin valve film comprising a first ferromagnetic layer, a non-magnetic layer, a second ferromagnetic layer and an antiferromagnetic layer.

14. A process for producing a thin film magnetic head as claimed in claim 11, wherein in said etching step, said film having a magnetoresistance effect has a substantially rectangular shape, and a longitudinal direction of said film having a magnetoresistance effect is substantially parallel to a plane facing a magnetic recording medium.

15. A process for producing a thin film magnetic head as claimed in claim 11, wherein in said etching step, said film having a magnetoresistance effect has a substantially rectangular shape, and a longitudinal direction of said film having a magnetoresistance effect is substantially perpendicular to a plane facing a magnetic recording medium.