US5094979A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of fabricating semiconductor device
Assignee: Mitsubishi Electric Corp
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Filing: 1991-05-06
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Granted: 1992-03-10
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Expires: 2011-05-06
Abstract
Abstract In a method of fabricating a semiconductor device, a conductive thin film is first removed by anisotropic etching through masks of electrodes having fine patterns. Thus, the conductive thin film is prevented from side etching in electrode portions, to thereby prevent electrode separation and V EBF failure. Then, the electrodes are covered with a resist film, to remove a part of the conductive thin film left on a concave step portion of a non-electrode forming region by isotropic etching. Thus, a problem of shorting across a base and an emitter caused by movement on the basis of separation of the conductive thin film is solved.
Inventors
- 👤 Yuuji Kusano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 10:08
CPC Classifications
H; H10; H10D; H10D10/00; H10D10/01; H10D10/051; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/056; H10W20/057
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
199 words
A method of fabricating a semiconductor device having fine pattern electrode structure, comprising: a step of forming an insulating layer over an electrode forming region and a non-electrode forming region on a semiconductor layer, said insulating layer having contact holes in said electrode forming region and a concave step portion in said non-electrode forming region; a step of forming a conductor layer having substantially uniform thickness on said semiconductor layer to cover said insulating layer and electrically connecting said conductor layer to said semiconductor layer through said contact holes; a step of forming a conductive thin film on said conductor layer; a step of forming electrodes on said electrode forming region of said conductive thin film; a step of selectively removing said conductive thin film by anisotropic etching through said electrodes serving as masks; a step of removing a part of said conductive thin film unremoved in said anisotropic etching step and left on a concave step portion of said conductor layer by isotropic etching in a state of covering said electrodes with a resist film; and a step of removing said resist film and thereafter selectively removing said conductor layer by etching through said electrodes serving as masks.
Claim 2
Independent Claim
199 words
A method of fabricating a semiconductor device having fine pattern electrode structure, comprising: a step of forming an insulating layer over an electrode forming region and a non-electrode forming region on a semiconductor layer, said insulating layer having contact holes in said electrode forming region and a concave step portion in said non-electrode forming region; a step of forming a conductor layer having substantially uniform thickness on said semiconductor layer to cover said insulating layer and electrically connecting said conductor layer to said semiconductor layer through said contact holes; a step of forming a conductive thin film on said conductor layer; a step of forming electrodes on said electrode forming region of said conductive thin film; a step of selectively removing said conductive thin film by anisotropic etching through said electrodes serving as masks; a step of removing a part of said conductive thin film unremoved in said anisotropic etching step and left on a concave step portion of said conductor layer by isotropic etching in a state of covering said electrodes with a resist film; and a step of removing said resist film and thereafter selectively removing said conductor layer by etching through said electrodes serving as masks.
Claim 3
Dependent Claim
30 words
A method of fabricating a semiconductor device in accordance with claim 1, comprising: providing a base electrode and an emitter electrode in the form of stripes as said electrodes respectively.
Claim 4
Dependent Claim
19 words
A method of fabricating a semiconductor device in accordance with claim 1, comprising forming said electrodes by electrolytic plating.
Claim 5
Dependent Claim
35 words
A method of fabricating a semiconductor device in accordance with claim 3, comprising forming said conductive thin film by sputtering, to be employed as a current path in formation of said electrodes by electrolytic plating.
Claim 6
Dependent Claim
39 words
A method of fabricating a semiconductor device in accordance with claim 3, wherein said conductor film is a barrier metal layer for preventing said semiconductor layer from intrusion of material atoms forming said electrodes and said conductive thin film.
References Cited (Backward Citations)
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JPS5679451A
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US4816424A
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