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US3763476A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for storing and reading out charge in an insulating layer

Assignee: General Electric Co
•
Filing: 1972-03-15
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Granted: 1973-10-02
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Expires: 1992-03-15
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Abstract

Abstract A diode storage array, including a diode array on one face of a semiconductor wafer, an insulating layer overlying the opposite face of said wafer and a conductive layer overlying the insulating layer, is written upon by irradiating the conductive layer side of said wafer to induce charge storage in the insulating layer. The radiation may be high energy photons, a scanned electron beam or electrons from a photo-emitter. Readout is accomplished by irradiating the target with lower energy radiation to form electron-hole pairs in the wafer. The holes are selectively driven to the diode side of the wafer under the control of the stored charge where selected, reverse biased, diodes are discharged. Subsequent scanning of the diode array by an electron beam produces a variable output signal, indicative of the information stored. Since the charge on the insulating layer is not dissipated, the information can be read as often as desired.

Inventors

  • 👤 R Wilson
  • 👤 G Possin
  • 👤 G Ellis

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 06:41
CPC Classifications
G; G11; G11C; G11C11/00; G11C11/21; G11C11/23; G11C13/00; G11C13/04; G11C13/048; H; H01; H01J; H01J31/00; H01J31/08; H01J31/26; H01J31/28; H01J31/283; Y; Y10; Y10S; Y10S148/00; Y10S148/026; Y10S148/05

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 63 words
An information storage target comprising: a substrate of a first type conductivity semiconductor having first and second opposite sides; a diode array formed on said first side; an insulating layer, overlying said second side, for storing information in the form of electric charge; and a conductive layer, overlying said insulating layer, for controlling the writing and erasing of information in said insulating layer.
Claim 2
Dependent Claim 63 words
An information storage target comprising: a substrate of a first type conductivity semiconductor having first and second opposite sides; a diode array formed on said first side; an insulating layer, overlying said second side, for storing information in the form of electric charge; and a conductive layer, overlying said insulating layer, for controlling the writing and erasing of information in said insulating layer.
Claim 3
Independent Claim 125 words
The method of writing, storing, reading and erasing information in a diode array target, containing a diode array on one face of a semiconductor wafer, an insulating layer overlying the opposite face of said wafer, and a transparent, conductive layer overlying the insulating layer, comprising the steps of: selectively irradiating the insulating layer to induce mobile electrons therein; drawing off said mobile electrons to selectively charge said insulating layer by biasing said conductive layer to one polarity; inducing electron-hole pairs in said wafer; preventing recombination of said pairs and allowing at least one of said electrons and holes to diffuse to the diode side of said wafer; and scanning the diode side of said wafer with an electron beam to read out said stored information.
Claim 4
Independent Claim 125 words
The method of writing, storing, reading and erasing information in a diode array target, containing a diode array on one face of a semiconductor wafer, an insulating layer overlying the opposite face of said wafer, and a transparent, conductive layer overlying the insulating layer, comprising the steps of: selectively irradiating the insulating layer to induce mobile electrons therein; drawing off said mobile electrons to selectively charge said insulating layer by biasing said conductive layer to one polarity; inducing electron-hole pairs in said wafer; preventing recombination of said pairs and allowing at least one of said electrons and holes to diffuse to the diode side of said wafer; and scanning the diode side of said wafer with an electron beam to read out said stored information.
Claim 5
Dependent Claim 43 words
The method as set forth in claim 2 and further comprising the steps of: biasing said conductive layer to a second, opposite polarity; and irradiating the insulating layer to induce mobile electrons in said insulator for neutralizing the charge on said insulating layer.
Claim 6
Dependent Claim 20 words
The method as set forth in claim 2 wherein said inducing step comprises: irradiating said target with photons of light.
Claim 7
Dependent Claim 36 words
The method as set forth in claim 2 wherein the step of selectively irradiating comprises: selectively irradiating the insulating layer with an electron beam penetrating said conductive layer to induce mobile electrons in said insulating layer.
Claim 8
Dependent Claim 111 words
An information storage system comprising a semiconductor diode array target comprising a planar semiconductor substrate having a diode array on one side and an insulating layer covering the opposite side; means for storing information in the form of electric charge in said insulating layer; means for irradiating said opposite side of said target for inducing electron-hole pairs in said substrate, said stored charge preventing recombination of said pairs to allow diffusion of at least one of said electrons and holes toward the diode array side of said target, thereby transferring the information from one side of the target to the other; and means for reading said information from said diode array.
Claim 9
Dependent Claim 111 words
An information storage system comprising a semiconductor diode array target comprising a planar semiconductor substrate having a diode array on one side and an insulating layer covering the opposite side; means for storing information in the form of electric charge in said insulating layer; means for irradiating said opposite side of said target for inducing electron-hole pairs in said substrate, said stored charge preventing recombination of said pairs to allow diffusion of at least one of said electrons and holes toward the diode array side of said target, thereby transferring the information from one side of the target to the other; and means for reading said information from said diode array.
Claim 10
Dependent Claim 63 words
The information storage system as recited in claim 6 wherein said target further comprises a transparent, conductive lAyer overlying said insulating layer and said means for storing information comprises: a source of electron beam for irradiating selected portions of said insulating layer; and bias means coupled to said transparent, conductive layer and said substrate for biasing said conductive layer relative to said substrate.
Claim 11
Dependent Claim 32 words
The information storage system as set forth in claim 6 wherein said means for reading said information comprises: a source of an electron beam for irradiating selected portions of said diode array.
Claim 12
Dependent Claim 22 words
The information storage system as set forth in claim 6 wherein said means for irradiating said target comprises a source of light.
Claim 13
Dependent Claim 15 words
The information storage system as set forth in claim 9 wherein said light is blue.

References Cited (Backward Citations)

US3440476A Cited
US3576392A Cited
US3668473A Cited
US3701979A Cited
US3676715A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-10-01 1977-04-02 1977-10-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-10-01 1981-04-02 1981-10-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-10-01 1985-04-02 1985-10-02 $7700.00 Window Closed / Lapsed

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