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US4563227A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for manufacturing a semiconductor device

Assignee: Panasonic Holdings Corp
•
Filing: 1984-10-12
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Granted: 1986-01-07
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Expires: 2004-10-12
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Abstract

Abstract The invention provides a method for manufacturing a semiconductor device, wherein a semiconductor substrate is vertically etched to form a groove, antioxidant insulating films are formed on the side walls of the groove, and local oxidation is performed. Lateral extrusion of an oxide film which is a so-called bird's beak and a projection of the oxide film which is a so-called bird's head are substantially eliminated. As a result, the active region of the transistor, that is, the element formation region may not be narrowed, providing high packing density and high precision. Furthermore, the surface of the semiconductor substrate is flattened to prevent short-circuiting and disconnections of wiring layers. Stable manufacturing process provides a high yield of the semiconductor device. Electrical characteristics of the semiconductor device are greatly improved.

Inventors

  • 👤 Hiroyuki Sakai
  • 👤 Kenji Kawakita
  • 👤 Tsutomu Fujita
  • 👤 Toyoki Takemoto

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 20:40
CPC Classifications
H; H10; H10W; H10W10/00; H10W10/01; H10W10/011; H10W10/014; H10W10/0145; H10W10/10; H10W10/17

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 161 words
A method of manufacturing an intermediate product for use in manufacturing a semiconductor device, comprising the steps of: (a) sequentially forming a first insulating film and a first antioxidant insulating film on a semiconductor region of one conductivity type; (b) selectively etching said first antioxidant insulating film and said first insulating film to form an opening; (c) substantially vertically etching said semiconductor region by an anisotropic dry etching method in the pattern of said opening formed in first antioxidant insulating film to form a groove having sidewalls and a bottom; (d) side etching said first insulating film using said first antioxidant insulating film as a mask to form side etched portions; (e) forming second antioxidant insulating film portions on the side walls of said groove including said side etched portions of said semiconductor region and excluding the bottom of said groove; and (f) oxidizing a portion of said semiconductor region defining said groove so as to form a third insulating film.
Claim 2
Independent Claim 161 words
A method of manufacturing an intermediate product for use in manufacturing a semiconductor device, comprising the steps of: (a) sequentially forming a first insulating film and a first antioxidant insulating film on a semiconductor region of one conductivity type; (b) selectively etching said first antioxidant insulating film and said first insulating film to form an opening; (c) substantially vertically etching said semiconductor region by an anisotropic dry etching method in the pattern of said opening formed in first antioxidant insulating film to form a groove having sidewalls and a bottom; (d) side etching said first insulating film using said first antioxidant insulating film as a mask to form side etched portions; (e) forming second antioxidant insulating film portions on the side walls of said groove including said side etched portions of said semiconductor region and excluding the bottom of said groove; and (f) oxidizing a portion of said semiconductor region defining said groove so as to form a third insulating film.
Claim 3
Dependent Claim 23 words
A method according to claim 1, wherein said first antioxidant insulating film and said second antioxidant insulating film portions comprise silicon nitride films.
Claim 4
Dependent Claim 48 words
A method according to claim 1, wherein said step (e) comprises forming a second antioxidant insulating film to cover the entire surface, and thereafter partially removing said second antioxidant insulating film by an anisotropic dry etching method to leave said second antioxidant insulating film portions on said sidewalls.
Claim 5
Dependent Claim 28 words
A method according to claim 1, wherein a second insulating film is formed before said second antioxidant insulating film portions is formed on the sidewalls of said groove.
Claim 6
Independent Claim 166 words
A method of manufacturing an intermediate product for use in manufacturing a semiconductor device, comprising the steps of: (a) sequentially forming a first insulating film and a first antioxidant insulating film on a semiconductor region of one conductivity type; (b) selectively etching said first antioxidant insulating film and said first insulating film to form an opening; (c) isotropically etching said semiconductor region using said first antioxidant insulating film and said first insulating film as a mask to form side etched portions; (d) substantially vertically etching said semiconductor region by an anisotropic dry etching method in the pattern of said opening formed in said first antioxidant insulating film to form a groove having a sidewall and a bottom; (e) forming second antioxidant insulating film portions on the side walls of said groove including said side etched portions of said semiconduct or region and excluding the bottom thereof; and (f) oxidizing a portion of said semiconductor region defining said groove so as to form a third insulating film.
Claim 7
Independent Claim 166 words
A method of manufacturing an intermediate product for use in manufacturing a semiconductor device, comprising the steps of: (a) sequentially forming a first insulating film and a first antioxidant insulating film on a semiconductor region of one conductivity type; (b) selectively etching said first antioxidant insulating film and said first insulating film to form an opening; (c) isotropically etching said semiconductor region using said first antioxidant insulating film and said first insulating film as a mask to form side etched portions; (d) substantially vertically etching said semiconductor region by an anisotropic dry etching method in the pattern of said opening formed in said first antioxidant insulating film to form a groove having a sidewall and a bottom; (e) forming second antioxidant insulating film portions on the side walls of said groove including said side etched portions of said semiconduct or region and excluding the bottom thereof; and (f) oxidizing a portion of said semiconductor region defining said groove so as to form a third insulating film.
Claim 8
Dependent Claim 23 words
A method according to claim 5, wherein said first antioxidant insulating film and said second antioxidant insulating film portions comprise silicon nitride films.
Claim 9
Dependent Claim 50 words
A method according to claim 5, wherein said step (e) comprises forming a second antioxidant insulating film on the entire surface, and thereafter partially removing said second antioxidant insulating film to leave said second antioxidant insulating film portions on the side surfaces of said groove including said side etched portions.
Claim 10
Dependent Claim 31 words
A method according to claim 5, wherein a second insulating film is formed on said sidewalls before said second antioxidant insulating film portions are formed on the sidewalls of said groove.
Claim 11
Independent Claim 183 words
A method of manufacturing an intermediate product for use in manufacturing a semiconductor device, comprising the steps of: (a) sequentially forming a first insulating film and a first antioxidant insulating film on a semiconductor region of one conductivity type; (b) selectively etching said first antioxidant insulating film and said first insulating film to form an opening; (c) isotropically etching said semiconductor region using said first antioxidant insulating film and said first insulating film as a mask to form side etched portions; (d) substantially vertically etching said semiconductor region by an anisotropic dry etching method in the pattern of said opening of said first antioxidant insulating film to form a groove having sidewalls and a bottom; (e) doping an impurity in a portion of said semiconductor region below said groove to form a high concentration P-type semiconductor region; (f) forming second antioxidant insulating film portions on sidewalls of said groove including said side etched portions of said semiconductor region and excluding the bottom of said groove; and (g) oxidizing a portion of said semiconductor region defining said groove to form a third insulating film.
Claim 12
Independent Claim 183 words
A method of manufacturing an intermediate product for use in manufacturing a semiconductor device, comprising the steps of: (a) sequentially forming a first insulating film and a first antioxidant insulating film on a semiconductor region of one conductivity type; (b) selectively etching said first antioxidant insulating film and said first insulating film to form an opening; (c) isotropically etching said semiconductor region using said first antioxidant insulating film and said first insulating film as a mask to form side etched portions; (d) substantially vertically etching said semiconductor region by an anisotropic dry etching method in the pattern of said opening of said first antioxidant insulating film to form a groove having sidewalls and a bottom; (e) doping an impurity in a portion of said semiconductor region below said groove to form a high concentration P-type semiconductor region; (f) forming second antioxidant insulating film portions on sidewalls of said groove including said side etched portions of said semiconductor region and excluding the bottom of said groove; and (g) oxidizing a portion of said semiconductor region defining said groove to form a third insulating film.
Claim 13
Dependent Claim 15 words
A method according to claim 9, wherein said high-concentration semiconductor region comprises a channel stopper.
Claim 14
Dependent Claim 40 words
A method according to claim 9, wherein an impurity is doped in an island region surrounded by said third insulating film so as to form a low-concentration semiconductor region having a different conductivity type than that of said semiconductor region.
Claim 15
Independent Claim 218 words
A method of manufacturing an intermediate product for use in manufacturing a semiconductor device, comprising the steps of: (a) sequentially forming a first insulating film and a first antioxidant insulating film on a semiconductor region initially of one conductivity type; (b) selectively etching said first antioxidant insulating film and said first insulating film to form a generally annular opening; (c) isotropically etching said semiconductor region using said first antioxidant insulating film and said first insulating film as a mask to form side etched portions; (d) substantially vertically etching said semiconductor region by an anisotropic dry etching method in the pattern of said generally annular opening of said first antioxidant insulating film to form a generally annular groove having sidewalls and a bottom; (e) forming second antioxidant insulating film portions on the sidewalls of said groove including said side etched portions of said semiconductor region and excluding the bottom of said groove; (f) oxidizing portions of said semiconductors region defining said groove to form a third insulating film; and (g) forming a base and an emitter in an island region of said semiconductor region surrounded by said third insulating film, such that sidewalls of said base are entirely in contact with said third insulating film and those of said emitter are partially in contact with said third insulating film.
Claim 16
Independent Claim 218 words
A method of manufacturing an intermediate product for use in manufacturing a semiconductor device, comprising the steps of: (a) sequentially forming a first insulating film and a first antioxidant insulating film on a semiconductor region initially of one conductivity type; (b) selectively etching said first antioxidant insulating film and said first insulating film to form a generally annular opening; (c) isotropically etching said semiconductor region using said first antioxidant insulating film and said first insulating film as a mask to form side etched portions; (d) substantially vertically etching said semiconductor region by an anisotropic dry etching method in the pattern of said generally annular opening of said first antioxidant insulating film to form a generally annular groove having sidewalls and a bottom; (e) forming second antioxidant insulating film portions on the sidewalls of said groove including said side etched portions of said semiconductor region and excluding the bottom of said groove; (f) oxidizing portions of said semiconductors region defining said groove to form a third insulating film; and (g) forming a base and an emitter in an island region of said semiconductor region surrounded by said third insulating film, such that sidewalls of said base are entirely in contact with said third insulating film and those of said emitter are partially in contact with said third insulating film.

References Cited (Backward Citations)

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US4187125A Cited
US4313255A Cited
JPS5612749A Cited
US4272308A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-01-06 1989-07-08 1990-01-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-01-06 1993-07-08 1994-01-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-01-06 1997-07-08 1998-01-07 $7700.00 Window Closed / Lapsed

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