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US5789276A Expired / Lapsed US ⏱️ 0.0 years remaining

Optical FET

Assignee: International Business Machines Corp
•
Filing: 1995-12-08
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Granted: 1998-08-04
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Expires: 2015-12-08
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Abstract

Abstract An optical FET includes one or more light-responsive diodes stacked on the gate. Each diode includes a planar (horizontal) junction. The number of diodes is chosen to achieve a desired gate to source potential difference. An electrical connection connects the diode(s) to the source of the FET.

Inventors

  • 👤 James Marc Leas
  • 👤 Jack Allan Mandelman

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 01:41
CPC Classifications
H; H10; H10D; H10D12/00; H10W; H10W90/00; H10F; H10F30/00; H10F30/20; H10F30/21; H10F30/28; H10F30/285; H10F30/2863

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 146 words
A method of forming a light-responsive FET, comprising steps of: providing a semiconductor substrate; depositing a dielectric layer on said semiconductor substrate; forming a gate on said dielectric layer and a light-responsive diode vertically adjacent said gate, said light-responsive diode comprising a planar junction, said step of forming comprising: depositing a first layer of semiconductor material on said dielectric layer, doping a first portion of said first layer of semiconductor material adjacent said dielectric layer with a first concentration of a first dopant type, doping a second portion of said first layer of semiconductor material adjacent said first portion with a second concentration of said first dopant type, depositing a second layer of semiconductor material on said first layer of semiconductor material, and doping said second layer of semiconductor material with a second dopant type; and forming a source and a drain in said semiconductor substrate.
Claim 2
Independent Claim 146 words
A method of forming a light-responsive FET, comprising steps of: providing a semiconductor substrate; depositing a dielectric layer on said semiconductor substrate; forming a gate on said dielectric layer and a light-responsive diode vertically adjacent said gate, said light-responsive diode comprising a planar junction, said step of forming comprising: depositing a first layer of semiconductor material on said dielectric layer, doping a first portion of said first layer of semiconductor material adjacent said dielectric layer with a first concentration of a first dopant type, doping a second portion of said first layer of semiconductor material adjacent said first portion with a second concentration of said first dopant type, depositing a second layer of semiconductor material on said first layer of semiconductor material, and doping said second layer of semiconductor material with a second dopant type; and forming a source and a drain in said semiconductor substrate.
Claim 3
Dependent Claim 58 words
The method of claim 1, wherein said step of doping a first portion comprises doping with a P-type dopant, wherein said step of doping a second portion comprises doping with a P-type dopant, wherein said first concentration is higher than said second concentration, and wherein said step of doping said second layer comprises doping with an N-type dopant.
Claim 4
Independent Claim 71 words
A method of forming a light-responsive FET, comprising steps of: providing a semiconductor substrate; depositing a dielectric layer on said semiconductor substrate; forming a gate on said dielectric layer; forming a light-responsive diode vertically adjacent said gate, said light-responsive diode comprising a planar junction; forming a source and a drain in said semiconductor substrate; forming an ohmic contact on said light-responsive diode; and forming another light-responsive diode on said ohmic contact.
Claim 5
Independent Claim 71 words
A method of forming a light-responsive FET, comprising steps of: providing a semiconductor substrate; depositing a dielectric layer on said semiconductor substrate; forming a gate on said dielectric layer; forming a light-responsive diode vertically adjacent said gate, said light-responsive diode comprising a planar junction; forming a source and a drain in said semiconductor substrate; forming an ohmic contact on said light-responsive diode; and forming another light-responsive diode on said ohmic contact.
Claim 6
Independent Claim 81 words
A method of forming a light-responsive FET, comprising steps of: (a) providing a semiconductor substrate; (b) forming a dielectric layer on said semiconductor substrate; (c) forming a gate on said dielectric layer; (d) forming a light-responsive diode vertically adjacent and self-aligned to said gate, said light-responsive diode comprising a planar junction; and (e) forming a source and a drain in said semiconductor substrate, wherein said step (e) comprises forming said source and drain self-aligned to said gate and said light-responsive diode.
Claim 7
Independent Claim 81 words
A method of forming a light-responsive FET, comprising steps of: (a) providing a semiconductor substrate; (b) forming a dielectric layer on said semiconductor substrate; (c) forming a gate on said dielectric layer; (d) forming a light-responsive diode vertically adjacent and self-aligned to said gate, said light-responsive diode comprising a planar junction; and (e) forming a source and a drain in said semiconductor substrate, wherein said step (e) comprises forming said source and drain self-aligned to said gate and said light-responsive diode.

References Cited (Backward Citations)

US4354309A Cited
US5235195A Cited
US5254480A Cited

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