US5100809A
Expired / Lapsed
US
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Method of manufacturing semiconductor device
Assignee: Mitsubishi Electric Corp
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Filing: 1991-02-05
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Granted: 1992-03-31
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Expires: 2011-02-05
Abstract
Abstract A silicon substrate (20) having a pnpn structure is soldered to a metal plate (10). A silicon oxide film (16) is naturally formed on the side surface of the silicon substrate during a process of removing defective part of the side surface, and a metal component penetrates into the silicon oxide film. The silicon substrate is dipped into an etchant to etch the silicon oxide film, so that a leak current through the metal component is effectively prevented.
Inventors
- 👤 Nobuhisa Nakashima
- 👤 Tokumitsu Sakamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 09:06
CPC Classifications
H; H10; H10P; H10P70/00; H10P70/10; H10P70/15; H10D; H10D62/00; H10D62/10; H10D62/102; H10D62/103; H10D62/104; H10D62/117; H10W; H10W70/00; H10W70/20; H10W74/00; H10W74/10; H10W74/131; H10W74/141
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
163 words
A method of manufacturing a semiconductor device, comprising the steps of; (a) fixing a major surface of a semiconductor substrate to a top surface of a metal plate, wherein said semiconductor substrate has at least one PN junction a part of which exposes at a side surface of said semiconductor substrate and said metal plate has a diameter larger than a diameter of said semiconductor substrate; (b) removing a shoulder part of said metal plate to thereby obtain a step configuration at a circumferential region in said top surface of said metal plate; (c) forming on said step configuration a mask layer resistant to etching; (d) etching a part of said semiconductor substrate exposing said side surface, wherein an oxide film is naturally formed on said side surface of said semiconductor substrate during said etching; (e) removing said oxide film from said side surface; (f) removing said mask layer; and (g) covering said side surface of said semiconductor substrate with a passivation film.
Claim 2
Independent Claim
163 words
A method of manufacturing a semiconductor device, comprising the steps of; (a) fixing a major surface of a semiconductor substrate to a top surface of a metal plate, wherein said semiconductor substrate has at least one PN junction a part of which exposes at a side surface of said semiconductor substrate and said metal plate has a diameter larger than a diameter of said semiconductor substrate; (b) removing a shoulder part of said metal plate to thereby obtain a step configuration at a circumferential region in said top surface of said metal plate; (c) forming on said step configuration a mask layer resistant to etching; (d) etching a part of said semiconductor substrate exposing said side surface, wherein an oxide film is naturally formed on said side surface of said semiconductor substrate during said etching; (e) removing said oxide film from said side surface; (f) removing said mask layer; and (g) covering said side surface of said semiconductor substrate with a passivation film.
Claim 3
Dependent Claim
22 words
The method of claim 1, wherein the step (b) comprises the step of: (b-1) removing said shoulder part with a mechanical tool.
Claim 4
Dependent Claim
47 words
The method of claim 1, wherein the step (a) comprises the steps of: (a-1) forming a solder layer on a whole region of said top surface of said metal plate; (a-2) soldering said semiconductor substrate on said solder layer through a first part of said solder layer.
Claim 5
Dependent Claim
39 words
The method of claim 3, wherein the step (b) comprises the steps of: (b-1) removing a shoulder part of said metal plate together with a second part of said solder layer circumscribing said first part of said solder layer.
Claim 6
Dependent Claim
34 words
The method of claim 4, wherein the step (d) comprises the step of: (d-1) etching said second part of said solder layer together with said part of said semiconductor substrate exposing said side surface.
Claim 7
Independent Claim
183 words
A method of manufacturing a semiconductor device, comprising the steps of: (a) fixing a major surface of a semiconductor substrate to a top surface of a metal plate, wherein said semiconductor substrate has at least one PN junction a part of which exposes at a side surface of said semiconductor substrate and said metal plate has a diameter larger than a diameter of said semiconductor substrate; (b) removing a shoulder part of said metal plate to thereby obtain a step configuration at a circumferential region in said top surface of said metal plate; (c) selectively removing a part of said semiconductor substrate exposing at said side surface to thereby obtain a slant surface at said side surface; (d) forming on said step configuration a mask layer resistant to etching; (e) etching said slant surface of said semiconductor substrate, wherein an oxide film is naturally formed on said surface of said semiconductor substrate during said etching; (f) removing said oxide film from said slant surface; (g) removing said mask layer; and (h) covering said slant surface of said semiconductor substrate with a passivation film.
Claim 8
Independent Claim
183 words
A method of manufacturing a semiconductor device, comprising the steps of: (a) fixing a major surface of a semiconductor substrate to a top surface of a metal plate, wherein said semiconductor substrate has at least one PN junction a part of which exposes at a side surface of said semiconductor substrate and said metal plate has a diameter larger than a diameter of said semiconductor substrate; (b) removing a shoulder part of said metal plate to thereby obtain a step configuration at a circumferential region in said top surface of said metal plate; (c) selectively removing a part of said semiconductor substrate exposing at said side surface to thereby obtain a slant surface at said side surface; (d) forming on said step configuration a mask layer resistant to etching; (e) etching said slant surface of said semiconductor substrate, wherein an oxide film is naturally formed on said surface of said semiconductor substrate during said etching; (f) removing said oxide film from said slant surface; (g) removing said mask layer; and (h) covering said slant surface of said semiconductor substrate with a passivation film.
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