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US4276114A Expired / Lapsed US ⏱️ 0.0 years remaining

Semiconductor substrate and a manufacturing method thereof

Assignee: De Nora SpA
•
Filing: 1979-02-06
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Granted: 1981-06-30
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Expires: 1999-02-06
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Abstract

Abstract This invention relates to a semiconductor substrate and a method of manufacturing the same. In a semiconductor manufacturing process for a Si single crystal wafer or the like, before the step of mirror polishing, the rear surface of a Si wafer is ground to form a damaged layer having a certain fixed thickness, the Si wafer is subsequently etched by chemical etching if desired, and the rear surface is further formed with an oxide film by thermal oxidation if desired, whereby a semiconductor substrate exhibiting an intense gettering effect is manufactured.

Inventors

  • 👤 Yukio Takano
  • 👤 Masahiko Ogirima
  • 👤 Shigeru Aoki
  • 👤 Michiyoshi Maki
  • 👤 Shigeo Kato

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 13:47
CPC Classifications
H; H10; H10P; H10P90/00; H10P90/12; H10P36/00; H10P36/03; H10P95/00; Y; Y10; Y10S; Y10S148/00; Y10S148/061; Y10S438/00; Y10S438/974; Y10T; Y10T428/00; Y10T428/31

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 91 words
A method of manufacturing a semiconductor substrate comprising the step of cutting a semiconductor crystal rod into the shape of a wafer, to obtain a semiconductor wafer, the step of grinding a rear surface of said semiconductor wafer with plane wheel means, to form a damaged layer whose maximum depth lies in a range of 2 μm to 20 μm in the rear surface, the step of etching the ground surface to decrease the curvature of said semiconductor wafer, and the step of mirror-polishing a front surface of the semiconductor wafer.
Claim 2
Independent Claim 91 words
A method of manufacturing a semiconductor substrate comprising the step of cutting a semiconductor crystal rod into the shape of a wafer, to obtain a semiconductor wafer, the step of grinding a rear surface of said semiconductor wafer with plane wheel means, to form a damaged layer whose maximum depth lies in a range of 2 μm to 20 μm in the rear surface, the step of etching the ground surface to decrease the curvature of said semiconductor wafer, and the step of mirror-polishing a front surface of the semiconductor wafer.
Claim 3
Dependent Claim 23 words
A method of manufacturing a semiconductor substrate according to claim 1, wherein the semiconductor wafer is heat-treated for oxidation after the etching step.
Claim 4
Dependent Claim 23 words
A method of manufacturing a semiconductor substrate according to claim 1 or 2, wherein said semiconductor substrate is a silicon single crystal substrate.
Claim 5
Dependent Claim 26 words
A method of manufacturing a semiconductor substrate according to claim 1 or 2 wherein said semiconductor substrate is provided with a semiconductor epitaxial growth layer thereon.
Claim 6
Dependent Claim 24 words
A method of manufacturing a semiconductor substrate according to claim 1, wherein said semiconductor substrate is provided with at least one semiconductor device thereon.
Claim 7
Dependent Claim 37 words
A method of manufacturing a semiconductor substrate according to claim 1 wherein the grinding step forms the damaged layer of a maximum depth of 2 μm to 15 μm in the rear surface of said semiconductor substrate.
Claim 8
Dependent Claim 32 words
A method of manufacturing a semiconductor substrate according to claim 1 or 2 wherein the grinding step is carried out with plane wheel means of less than a grit size of 2000.
Claim 9
Dependent Claim 24 words
A method of manufacturing a semiconductor substrate according to claim 3, wherein said semiconductor substrate is provided with a semiconductor epitaxial growth layer thereon.
Claim 10
Dependent Claim 24 words
A method of manufacturing a semiconductor substrate according to claim 3, wherein said semiconductor substrate is provided with at least one semiconductor device thereon.
Claim 11
Dependent Claim 37 words
A method of manufacturing a semiconductor substrate according to claim 3, wherein the grinding step forms the damaged layer of a maximum depth of 2 μm to 15 μm in the rear surface of said semiconductor substrate.
Claim 12
Dependent Claim 30 words
A method of manufacturing a semiconductor substrate according to claim 3, wherein the grinding step is carried out with plane wheel means of less than a grit size of 2000.

References Cited (Backward Citations)

US3041226A Cited
US3009841A Cited
US3266961A Cited
US3128213A Cited
US3436286A Cited
US3342652A Cited
US3615955A Cited
US3888053A Cited
US3923567A Cited
US4144099A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-06-29 1984-12-29 1985-06-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-06-29 1988-12-29 1989-06-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-06-29 1992-12-29 1993-06-30 $7700.00 Window Closed / Lapsed

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