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US4536946A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for fabricating semiconductor photodetector

Assignee: Individual
•
Filing: 1983-12-13
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Granted: 1985-08-27
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Expires: 2003-12-13
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Abstract

Abstract A semiconductor photodetector, and a process for producing a semiconductor photodetector, having a shielding gate region isolated from drain or source regions with only a small junction capacitance therebetween. The photodetector is implemented with a vertical static induction transistor. In the static induction transistor, a control gate region is formed on a first principal surface of a silicon wafer. The shielding gate region is formed on the principal surface surrounding the control gate region. At least one first principal electrode region is formed on the first principal surface between the control region and the shielding gate region. A second principal electrode region is formed on a second principal surface of the wafer on the side thereof opposite the first principal electrode region. The shielding gate region is formed in the silicon wafer at a position deeper than the first principal electrode region.

Inventors

  • 👤 Junichi Nishizawa
  • 👤 Sobei Suzuki
  • 👤 Takashige Tamamushi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 17:55
CPC Classifications
H; H10; H10F; H10F39/00; H10F39/011; H10F39/026; H10D; H10D62/00; H10D62/10; H10D62/17; H10D62/343; H10F39/10; H10F39/12; H10F39/196; H10F39/80; H10F39/802; H10F39/805; H10F39/8057

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 167 words
A process for producing a photodetector comprising a vertical static induction transistor, comprising the steps of: formaing a control gate region on a first principal surface of a silicon wafer; forming a shielding gate region on said first principal surface surrounding said control gate region; forming at least one first principal electrode region on said first principal surface in an area between said control region and said shielding gate region; forming a second principal electrode region on a second principal surface of said silicon wafer on the side opposite said first principal electrode region, said first electrode region and said shielding gate region being formed on said first principal surface in such a manner that a top of each of said regions is flush with said first principal surface; and forming an oxide film on the upper part of said shielding gate region by selective oxidation so that remaining portions of said shielding gate region are deeper in said silicon wafer than said first principal electrode region.
Claim 2
Dependent Claim 167 words
A process for producing a photodetector comprising a vertical static induction transistor, comprising the steps of: formaing a control gate region on a first principal surface of a silicon wafer; forming a shielding gate region on said first principal surface surrounding said control gate region; forming at least one first principal electrode region on said first principal surface in an area between said control region and said shielding gate region; forming a second principal electrode region on a second principal surface of said silicon wafer on the side opposite said first principal electrode region, said first electrode region and said shielding gate region being formed on said first principal surface in such a manner that a top of each of said regions is flush with said first principal surface; and forming an oxide film on the upper part of said shielding gate region by selective oxidation so that remaining portions of said shielding gate region are deeper in said silicon wafer than said first principal electrode region.
Claim 3
Dependent Claim 27 words
The process according to claim 1 wherein a plurality of units of said static induction transistor are formed in an array pattern on a single silicon wafer.
Claim 4
Dependent Claim 20 words
The process according to claim 2, wherein said plurality of static induction transistor units are arranged in a two-dimensional array.
Claim 5
Dependent Claim 21 words
The process according to claim 2 wherein said plurality of static induction transistor units are formed in a one-dimensional linear configuration.
Claim 6
Dependent Claim 17 words
The process according to claim 1, wherein a single unit of said static induction transistor is formed.
Claim 7
Dependent Claim 183 words
A process for producing a photodetector comprising a vertical static induction transistor, comprising the steps of: forming a control gate region on a first principal surface of a silicon wafer; forming a shielding gate region on said first principal surface surrounding said control gate region; forming at least one first principal electrode region formed on said first principal surface in an area between said control region and said shielding gate region; forming a second principal electrode region on a second principal surface of said silicon wafer on the side opposite said first principal electrode region, wherein said step of forming said at least one first principal electrode region on said first principal surface comprises forming a top surface of said region flush with said first principal surface, etching a notch in said first principal surface, said shielding gate region being formed at an apex of said notch, and forming an oxide film by oxidizing an upper part of said shielding gate region, and wherein remaining portions of said shielding gate region are deeper in said silicon wafer than said first principal electrode region.
Claim 8
Dependent Claim 183 words
A process for producing a photodetector comprising a vertical static induction transistor, comprising the steps of: forming a control gate region on a first principal surface of a silicon wafer; forming a shielding gate region on said first principal surface surrounding said control gate region; forming at least one first principal electrode region formed on said first principal surface in an area between said control region and said shielding gate region; forming a second principal electrode region on a second principal surface of said silicon wafer on the side opposite said first principal electrode region, wherein said step of forming said at least one first principal electrode region on said first principal surface comprises forming a top surface of said region flush with said first principal surface, etching a notch in said first principal surface, said shielding gate region being formed at an apex of said notch, and forming an oxide film by oxidizing an upper part of said shielding gate region, and wherein remaining portions of said shielding gate region are deeper in said silicon wafer than said first principal electrode region.
Claim 9
Dependent Claim 27 words
The process according to claim 6, wherein a plurality of units of said static induction transistor are formed in an array pattern on a single silicon wafer.
Claim 10
Dependent Claim 19 words
The process according to claim 7, wherein said plurality of static induction transistors are formed in a two-dimensional array.
Claim 11
Dependent Claim 21 words
The process according to claim 7, wherein said plurality of static induction transistor units are formed in a one-dimensional linear configuration.
Claim 12
Dependent Claim 17 words
The process according to claim 6, wherein a single unit of said static induction transistor is formed.

References Cited (Backward Citations)

US4449284A Cited
US4377900A Cited
US4409725A Cited
US4505022A Cited
US4466175A Cited
US4499654A Cited
US4502203A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-08-26 1989-02-25 1989-08-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-08-26 1993-02-25 1993-08-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-08-26 1997-02-25 1997-08-27 $7700.00 Window Closed / Lapsed

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