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Patent US3654531A successfully refreshed from Google Patents.
US3654531A
Expired / Lapsed
US
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Electronic switch utilizing a semiconductor with deep impurity levels
Assignee: AT&T Inc
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Filing: 1969-10-24
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Granted: 1972-04-04
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Expires: 1989-10-24
Abstract
Abstract An electronic two-terminal switch is furnished by a metalsemiconductor-metal (MSM) layered structure, in which both of the metal layers form ohmic contacts with the semiconductor. The semiconductor is a single crystal, advantageously of silicon, characterized by a concentration of shallow impurity levels (typically donors) which is less than the concentration of deep impurity levels (''''traps''''). A three-terminal switch can be made therefrom in a planar semiconductor structure, by further providing the structure with a control electrode which is located between the ohmic contacts and which is insulated from the semiconductor.
Inventors
- 👤 Robert H Krambeck
- 👤 Peter T Panousis
- 👤 Robert J Strain
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:12
CPC Classifications
H; H10; H10D; H10D99/00; H10N; H10N70/00; H10N70/011; H10N70/041; H10N70/046; H10N70/20; H10N70/25; H10N70/253; H10N70/801; H10N70/821; H10N70/823; H10N70/881; H10N70/884; H10P; H10P95/00
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
181 words
An electronic switching circuit which comprises: a. an electronic switching device whose semiconductive portion consists of a monocrystalline semiconductor body having a uniform concentration of traps and a uniform net concentration of significant shallow impurity levels, the concentration of traps being a factor in the range of about 1.5 and 15 greater than the net concentration of shallow impurity levels; b. first and second noninjecting ohmic metal contacts in physical contact with the body, said contacts adapted for connection to the circuit; and c. electrical signal voltage means connected to at least one of the metal contacts for producing an electric field in the body between the contacts, the traps being characterized in that an increase in the electric field produces an increase in the emission probability of charge carriers from the traps relative to the capture probability of charge carriers by the traps, the concentration of traps being sufficient such that, in the absence of optical radiation incident on the body, the current flowing through the body between the contacts discontinuously increases when the signal voltage reaches a predetermined value.
Claim 2
Dependent Claim
181 words
An electronic switching circuit which comprises: a. an electronic switching device whose semiconductive portion consists of a monocrystalline semiconductor body having a uniform concentration of traps and a uniform net concentration of significant shallow impurity levels, the concentration of traps being a factor in the range of about 1.5 and 15 greater than the net concentration of shallow impurity levels; b. first and second noninjecting ohmic metal contacts in physical contact with the body, said contacts adapted for connection to the circuit; and c. electrical signal voltage means connected to at least one of the metal contacts for producing an electric field in the body between the contacts, the traps being characterized in that an increase in the electric field produces an increase in the emission probability of charge carriers from the traps relative to the capture probability of charge carriers by the traps, the concentration of traps being sufficient such that, in the absence of optical radiation incident on the body, the current flowing through the body between the contacts discontinuously increases when the signal voltage reaches a predetermined value.
Claim 3
Dependent Claim
43 words
The switching circuit recited in claim 1 in which the semiconductor body is essentially silicon, the concentration of traps is about 3 X 1016 per cm3 and the net concentration of significant shallow impurity levels is about 5 X 1015 donors per cm3.
Claim 4
Dependent Claim
21 words
The electronic switching circuit recited in claim 2 in which the traps are essentially gold atoms in the silicon semiconductor body.
Claim 5
Dependent Claim
92 words
An electronic switching circuit which comprises: a. the switching circuit recited in claim 1 in which the first and second ohmic contacts are located on a single major surface of the semiconductor body; b. an insulator layer on at least a portion of said major surface between the first and second metal contacts; c. an electrode layer disposed on the insulator layer; and d. conductive means for electrically connecting the signal voltage means to the electrode layer in order to produce the electric field in the body in response to the signal.
Claim 6
Dependent Claim
44 words
An electronic switching circuit according to claim 4 in which the semiconductor body is essentially silicon, the concentration of traps is about 3 X 1016 per cm3, and the net concentration of significant shallow impurity levels is about 5 X 1015 donors per cm3.
Claim 7
Dependent Claim
24 words
An electronic switching circuit according to claim 5 in which the traps are essentially deep levels of gold impurity in the silicon semiconductor body.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-04 | 1975-10-04 | 1976-04-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-04 | 1979-10-04 | 1980-04-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-04 | 1983-10-04 | 1984-04-04 | $7700.00 | Window Closed / Lapsed |