EP0206136A2
Expired / Lapsed
EP
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Semiconductor device manufacturing method
Assignee: Toshiba Corp
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Filing: 1986-06-12
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Granted: —
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Expires: 2006-06-12
Abstract
Abstract Disclosed is a semiconductor device manufacturing method comprising a first step of preparing a p-type semiconductor substrate (30), a second step of forming an oxide film pattern (32A) on the bottom surface of the semiconductor substrate (30), a third step of forming an n +- type diffusion regions (36A) by using a mask of the oxide film pattern (32A), and a fourth step of forming a first p-type diffusion region with a depth shallower than the n +- type diffusion regions (36A) in the bottom surface of the semiconductor substrate (30) after removal of the oxide film pattern (32A), forming a second p-type diffusion region in the upper surface of the semiconductor substrate (30). The manufacturing method further comprises a fifth step of removing a part of the semiconductor substrate (30) on the upper surface side by a predetermined thickness, before formation of the second p-type diffusion region.
Inventors
- 👤 Takashi Patent Division Fujiwara
- 👤 Ryoji Patent Division Tanoue
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 04:46
CPC Classifications
H; H10; H10D; H10D18/00; H10D18/01; H10D18/60; H10D62/00; H10D62/10; H10D62/13; H10D62/141; H10D62/142
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
178 words
A semiconductor device manufacturing method comprising: a first step of preparing a semiconductor substrate (30) of a first conductivity type having first and second surfaces; a second step of forming an oxide film pattern on the first surface of said semiconductor substrate (30); a third step of forming a first region (36A) of the first conductivity type in the first surface of said semiconductor substrate (30) by using a mask of said oxide film pattern (32A), .with a higher impurity concentration than said semiconductor substrate; and a fourth step of forming a second region (38A) of a second conductivity type in said first surface of said semiconductor substrate (30) with a depth shallower than said first region (36A) after removal of said oxide film pattern (32A), and forming a third region (38B) of the second conductivity type in the second surface of said semiconductor substrate (30); characterized by further comprising a fifth step of removing a part of said semiconductor substrate (30) on the second surface side by a predetermined thickness, before formation of said third region (38B).
Claim 2
Dependent Claim
178 words
A semiconductor device manufacturing method comprising: a first step of preparing a semiconductor substrate (30) of a first conductivity type having first and second surfaces; a second step of forming an oxide film pattern on the first surface of said semiconductor substrate (30); a third step of forming a first region (36A) of the first conductivity type in the first surface of said semiconductor substrate (30) by using a mask of said oxide film pattern (32A), .with a higher impurity concentration than said semiconductor substrate; and a fourth step of forming a second region (38A) of a second conductivity type in said first surface of said semiconductor substrate (30) with a depth shallower than said first region (36A) after removal of said oxide film pattern (32A), and forming a third region (38B) of the second conductivity type in the second surface of said semiconductor substrate (30); characterized by further comprising a fifth step of removing a part of said semiconductor substrate (30) on the second surface side by a predetermined thickness, before formation of said third region (38B).
Claim 3
Dependent Claim
37 words
A method according to claim 1, characterized in that said fifth step removes a part of said semiconductor substrate on the second surface side by the predetermined thickness greater than the depth of said first region (36A).
Claim 4
Dependent Claim
26 words
A method according to claim 2, characterized in that said fifth step includes a lapping process for lapping the second surface of said semiconductor substrate (30).
Claim 5
Dependent Claim
29 words
A method according to claim 3, characterized in that said fifth step includes an etching process for etching the second surface of said semiconductor substrate after said lapping process.
Claim 6
Dependent Claim
76 words
A method according to claim 2, characterized in that said second step includes a substep of forming an oxide film (32) of a uniform thickness covering the entire surface of said semiconductor substrate (30), a substep of forming a resist pattern (34) on the oxide film (32) over the first surface of said substrate (30), and a substep of removing the unmasked portions of said oxide film (32) after the formation of said resist pattern (34).
Claim 7
Dependent Claim
32 words
A method according to claim 1, characterized by further comprising a sixth step of forming a fourth region (40A; 40B; 40C; 40D) of the first conductivity type on said third region (38B).
Claim 8
Dependent Claim
69 words
A method according to claim 6, characterized in that said sixth step includes a substep of forming a layer (40) of the first conductivity type entirely covering said third region (38B), and a substep of selectively etching said layer (40) to leave part of said layer (40) at the location corresponding to said first region (36A), said layer part left serving as said fourth region (40A; 40B; 40C; 40D).
Claim 9
Dependent Claim
58 words
A method according to claim 6, characterized by further comprising a seventh step for forming a first electrode (46) in ohmic contact with said first and second regions (36A, 38A), a second electrode (48) in ohmic contact with said third region (38B), and a third electrode (44) in ohmic contact with said fourth region (40A; 40B; 40C; 40D).
References Cited (Backward Citations)
No citation records indexed.
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