US3852798A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electroluminescent device
Assignee: US Philips Corp
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Filing: 1973-03-12
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Granted: 1974-12-03
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Expires: 1993-03-12
Abstract
Abstract A monolithic semiconductor device having a electroluminescent diode and a photoresistor which controls the current in the diode. The device comprises in series a diode, a filter layer and a photoconductive layer, the forbidden bandwidth of the filter layer being between that of the diode and of the photoconductive layer.
Inventors
- 👤 J Leabailly
- 👤 J Dubois
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:20
CPC Classifications
H; H10; H10H; H10H20/00; H10H20/80; H10H20/81; H10D; H10D99/00
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
184 words
AN ELECTROLUMINESCENT DEVICE COMPRISING: A. A MONOLITHIC CRYSTALLINE SEMICONDUCTOR BODY, SAID BODY HAVING IN ELECTRICAL SERIES RELATIONSHIP I. A FIRST SURFACE REGION OF A FIRST CONDUCTIVITY TYPE, II. A SECOND REGION OF A SECOND CONDUCTIVITY TYPE OPPOSITE TO SAID FIRST TYPE AND ADJOINING THE FIRST REGION AND FORMING WITH THE LATTER A P-N JUNCTION HAVING ELECTROLUMINESCENT PROPERTIES AND CAPABLE OF EMITTING PHOTONS WITHIN A CERTAIN ENERGY RANGE WHEN CURRENT IS PASSED THROUGH THE P-N JUNCTION, III. A FILTER LAYER OF THE SECOND CONDUCTIVITY TYPE, AND IV. A PHOTOCONDUCTIVE SEMI-INSULATING LAYER OF THE SECOND CONDUCTIVITY TYPE AND HAVING A FORBIDDEN BANDWIDTH WHICH IS SMALLER THAN THE ENERGY OF THE PHOTONS EMITTED BY THE ELECTROLUMINESCENT JUNCTION, SAID FILTER LAYER HAVING A FORBIDDED BANDWITCH WHICH LIES BETWEEN THAT OF THE PHOTOCONDUCTIVE LAYER AND THE ENERGY OF THE PHOTONS EMITTED BY THE ELECTROLUMINESCENT JUNCTION, AND B. FIRST AND SECOND ELECTRODES CONNECTED TO THE BODY FOR PASSING CURRENT THROUGH THE SERIES CONNECTED REGIONS AND LAYERS WHEREBY THE PHOTON OUTPUT FROM THE DEVICE IS CONTROLLED BY THE RESISTANCE OF THE PHOTOCONDUCTIVE LAYER WHICH IN TURN IS CONTROLLED BY EXTERNAL ILLUMINATION.
Claim 2
Dependent Claim
184 words
AN ELECTROLUMINESCENT DEVICE COMPRISING: A. A MONOLITHIC CRYSTALLINE SEMICONDUCTOR BODY, SAID BODY HAVING IN ELECTRICAL SERIES RELATIONSHIP I. A FIRST SURFACE REGION OF A FIRST CONDUCTIVITY TYPE, II. A SECOND REGION OF A SECOND CONDUCTIVITY TYPE OPPOSITE TO SAID FIRST TYPE AND ADJOINING THE FIRST REGION AND FORMING WITH THE LATTER A P-N JUNCTION HAVING ELECTROLUMINESCENT PROPERTIES AND CAPABLE OF EMITTING PHOTONS WITHIN A CERTAIN ENERGY RANGE WHEN CURRENT IS PASSED THROUGH THE P-N JUNCTION, III. A FILTER LAYER OF THE SECOND CONDUCTIVITY TYPE, AND IV. A PHOTOCONDUCTIVE SEMI-INSULATING LAYER OF THE SECOND CONDUCTIVITY TYPE AND HAVING A FORBIDDEN BANDWIDTH WHICH IS SMALLER THAN THE ENERGY OF THE PHOTONS EMITTED BY THE ELECTROLUMINESCENT JUNCTION, SAID FILTER LAYER HAVING A FORBIDDED BANDWITCH WHICH LIES BETWEEN THAT OF THE PHOTOCONDUCTIVE LAYER AND THE ENERGY OF THE PHOTONS EMITTED BY THE ELECTROLUMINESCENT JUNCTION, AND B. FIRST AND SECOND ELECTRODES CONNECTED TO THE BODY FOR PASSING CURRENT THROUGH THE SERIES CONNECTED REGIONS AND LAYERS WHEREBY THE PHOTON OUTPUT FROM THE DEVICE IS CONTROLLED BY THE RESISTANCE OF THE PHOTOCONDUCTIVE LAYER WHICH IN TURN IS CONTROLLED BY EXTERNAL ILLUMINATION.
Claim 3
Dependent Claim
85 words
A device as set forth in claim 1, wherein the first electrode is connected to the first region and the econd electrode is connected to the photoconductive layer, the first region and first electrode are substantially transparent to and the filter layer is substantially absorbant of the emitted photons from the electroluminescent junction, and the first electrode, first and second regions and filter layer are substantially transparent to and the photoconductive layer is substantially absorbant of a portion of the spectrum of external ambient illumination.
Claim 4
Dependent Claim
63 words
A device as claimed in claim 1, wherein the material constituting the first and second regions and the material constituting the filter layer having different concentrations of common components and crystallise in the same crystal system, and the material constituting the filter layer and the material constituting the photoconductive layer have different concentrations of common components and crystallise in the same crystal system.
Claim 5
Dependent Claim
46 words
A device as claimed in claim 3, wherein at least a part of the filter layer is present in a buffer layer in which the concentrations of the said common components vary gradually between the values of said concentration on either side of the buffer layer.
Claim 6
Dependent Claim
33 words
A device as claimed in claim 1, wherein the filter layer consists of the same material as that of the second region of the semiconductor body, said material having a direct band structure.
Claim 7
Dependent Claim
48 words
A device as claimed in claim 1, wherein the filter layer has a thickness at least equal to three times the absorption distance 1/ Alpha , where Alpha is the absorption coefficient of the material of said filter layer for the photon energy emitted by the electroluminescent junction.
Claim 8
Dependent Claim
36 words
A device as claimed in claim 1, wherein the surface of the photoconductive layer which is reached by the external illumination is at least one order of magnitude larger than the surface of the electroluminescent junction.
Claim 9
Dependent Claim
31 words
A device as claimed in claim 2, wehrein the said first region has a convex outer surface through which the photons emitted by the junction emanates and the external illumination enters.
Claim 10
Dependent Claim
19 words
A device as claimed in claim 1 and comprising several isolated electroluminescent junctions integrated in a common crystalline support.
Claim 11
Dependent Claim
112 words
A device as claimed in claim 1, wherein the first region is p-type and the second region is n-type and the first and second regions are constituted of gallium arsenide phosphide GaAs1 xPx where x decreases from the value in the first and second regions to 0, and the photoconductive layer is constituted of gallium arsenide phosphide GaAs1 xPx, wherein 0 < x < 0.4, the filter layer is n-type and is constituted of GaAs1 xPx where x decreases from the value in the first and second regions to 0, and the photoconductive layer is constituted of compensated gallium arsenide GaAs which has a resistivity which lies betwen 102 and 108 ohm-cm.
Claim 12
Dependent Claim
77 words
A device as claimed in claim 1, wherein the first region is p-type and the second region is n-type and the first and second regions are constituted of gallium aluminum arsenide Ga1 xAlxAs, where 0.3 < x < 0.4, the filter layer is n-type and constituted of gallium aluminum arsenide Ga1 xAlxAs, where 0 < x < 0.3, and the photoconductive layer is constituted of compensated gallium arsEnide GaAs having a resistivity between 102 and 108 ohm-cm.
Claim 13
Dependent Claim
43 words
A device as claimed in claim 2, wherein the material of the photoconductive layer is compensated gallium arsenide in which the compensation is caused by the addition of an element from the group consisting of copper, iron, nickel, cobalt, manganese, chromium and oxygen.
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US3667007A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-12-02 | 1978-06-03 | 1978-12-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-02 | 1982-06-03 | 1982-12-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-02 | 1986-06-03 | 1986-12-03 | $7700.00 | Window Closed / Lapsed |