US3978509A
Expired / Lapsed
US
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Photosensitive semiconductor device
Assignee: US Philips Corp
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Filing: 1975-04-18
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Granted: 1976-08-31
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Expires: 1995-04-18
Abstract
Abstract A semiconductor device having a photosensitive semiconductor element, for example a photoresistor, having a photosensitive layer of high-ohmic material, preferably gold-compensated silicon, which is present on a high-ohmic substrate region and which is covered with a highly doped semiconductor surface layer. According to the invention, an epitaxial intermediate layer is present between the substrate region and the photosensitive layer and has a resistivity which lies between that of the photosensitive layer and that of the substrate region, while the surface layer, which is preferably partly etched away prior to the provision of the electrode, is grown epitaxially on the photosensitive layer.
Inventors
- 👤 Christian Gouin
- 👤 Gerard Gimine
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 23:24
CPC Classifications
H; H10; H10F; H10F30/00; H10F30/10; H10F99/00; H10P; H10P95/00; Y; Y10; Y10S; Y10S438/00; Y10S438/914; Y10S438/919
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
94 words
A semiconductor device having a photosensitive semiconductor element comprising a semiconductor body having a monocrystalline substrate region of low resistivity, and epitaxial photosensitive layer of doping material-compensated semiconductor material of a very high resistivity, an epitaxial intermediate layer disposed directly between and having a resistivity which lies between that of said substrate region and said photosensitive layer, an epitaxial semiconductor surface layer of low resistivity disposed over and at least partly covering said photosensitive layer, a first non-rectifying electrical contact on said substrate region, and a second non-rectifying electrical contact for said photosensitive layer.
Claim 2
Dependent Claim
94 words
A semiconductor device having a photosensitive semiconductor element comprising a semiconductor body having a monocrystalline substrate region of low resistivity, and epitaxial photosensitive layer of doping material-compensated semiconductor material of a very high resistivity, an epitaxial intermediate layer disposed directly between and having a resistivity which lies between that of said substrate region and said photosensitive layer, an epitaxial semiconductor surface layer of low resistivity disposed over and at least partly covering said photosensitive layer, a first non-rectifying electrical contact on said substrate region, and a second non-rectifying electrical contact for said photosensitive layer.
Claim 3
Dependent Claim
53 words
A semiconductor device as in claim 1, wherein said substrate region and said semiconductor layers provided thereon are all n-type and said photosensitive layer consists essentially of a semiconductor material which is compensated with a doping material having an active energy level near the center of the forbidden band of said semiconductor material.
Claim 4
Dependent Claim
27 words
A semiconductor device as in claim 2, wherein said substrate region and said semiconductor layers provided thereon are of silicon and said compensating doping material is gold.
Claim 5
Dependent Claim
31 words
A semiconductor device as in claim 3, wherein the level of said compensating doping material of said photosensitive layer is substantially equal to that of the donor concentration on said layer.
Claim 6
Dependent Claim
60 words
A semiconductor device as in claim 4, wherein said doping concentration of said substrate region is approximately 5×10 18 atoms/cm 3 , the average doping concentration of said intermediate layer is at least 10 16 and at most 5×10 17 atoms/cm 3 and the doping concentration of the epitaxial semiconductor surface layer is at least 10 20 atoms/cm 3 .
Claim 7
Dependent Claim
52 words
A semiconductor device as in claim 5, wherein said intermediate layer has a thickness of at least 5 and at most 20 microns, said photosensitive layer has a thickness of at least 10 microns and at most 20 microns, and said semiconductor surface layer has a thickness of at most 1 micron.
Claim 8
Dependent Claim
76 words
A method of manufacturing a semiconductor device as recited in claim 1, comprising the steps of providing successively in the same epitaxial growth process on said substrate said intermediate layer, photosensitive layer and semiconductor surface layer, such that surface layer has an original thickness of at least 5 microns and at most 10 microns, and then introducing said compensating doping material in the photosensitive layer by diffusion from one of the surfaces of the resulting structure.
Claim 9
Dependent Claim
23 words
A method as in claim 7, wherein silicon is used as a semiconductor material and gold is used as said compensating doping material.
Claim 10
Dependent Claim
33 words
A method as in claim 7, wherein, after the indiffusion of said compensating doping material said surface layer is partly etched away and then an electrode layer is provided on the etched surface.
Claim 11
Dependent Claim
84 words
A method as in claim 9, wherein, after the step of indiffusing said gold, said surface layer is etched down to a thickness of at least 4 and at most 5 microns, a metal layer on the remaining part of said surface layer, then shaping said metal layer in the desired electrode pattern, and then further etching parts of the surface layer not covered by said metal layer until the thickness of the remaining part of said surface layer is at most 1 micron.
References Cited (Backward Citations)
US3668555A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-31 | 1980-03-01 | 1980-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-31 | 1984-03-01 | 1984-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-31 | 1988-03-01 | 1988-08-31 | $7700.00 | Window Closed / Lapsed |