US4037244A
Expired / Lapsed
US
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Avalanche photodiode
Assignee: Thales SA
•
Filing: 1976-05-07
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Granted: 1977-07-19
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Expires: 1996-05-07
Abstract
Abstract An avalanche photodiode has an avalanche voltage relatively low. In one of the two elements of the junction there is a zone doped more heavily than said element and having the same conductivity type.
Inventors
- 👤 Baudouin DE Cremoux
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:10
CPC Classifications
H; H10; H10F; H10F30/00; H10F30/20; H10F30/21; H10F30/22; H10F30/225
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
93 words
An avalanche photodiode for detecting incident radiation of a predetermined wavelength comprising superimposed, a first layer of a first type of conductivity and a second layer of a second type of conductivity opposite to the first, said layers having respective superimposed central portions, and inserted in one of said central portions a third layer forming a rectifying junction with said first layer, said third layer having a high impurity concentration, so that the electrical avalanche phenomenon is localized preferentially in said third layer for reverse biasing predetermined voltage values applied to said diode.
Claim 2
Dependent Claim
93 words
An avalanche photodiode for detecting incident radiation of a predetermined wavelength comprising superimposed, a first layer of a first type of conductivity and a second layer of a second type of conductivity opposite to the first, said layers having respective superimposed central portions, and inserted in one of said central portions a third layer forming a rectifying junction with said first layer, said third layer having a high impurity concentration, so that the electrical avalanche phenomenon is localized preferentially in said third layer for reverse biasing predetermined voltage values applied to said diode.
Claim 3
Dependent Claim
49 words
A diode as claimed in claim 1, wherein said second layer is exposed to said radiation, and being made of a semiconductor material having a forbidden band width greater than that of the materials of said other layers so as to be transparent to the radiation to be detected.
Claim 4
Dependent Claim
36 words
A diode as claimed in claim 2, wherein the conductivity types of said layers are selected in such a way that the avalanche phenomenon is triggered off by the displacement of holes within said third zone.
Claim 5
Dependent Claim
31 words
A diode as claimed in claim 3, wherein the thickness of the third layer is sufficiently thin to be transparent to the radiation, the radiation being absorbed in the first layer.
Claim 6
Dependent Claim
69 words
A diode as claimed in claim 4, wherein said first layer has type n-conductivity, said second and third layers having type p-conductivity, the first layer having a doping concentration of the order of 10 16 at/cm 3 , said second and said third layers having doping concentrations of the order of 10 19 at/cm 3 , the thickness of the third layer being of the order of 0.1 micron.
Claim 7
Dependent Claim
21 words
A diode as claimed in claim 3, wherein said third layer is sufficiently thick to absorb the radiation to be detected.
Claim 8
Dependent Claim
41 words
A diode as claimed in claim 6, wherein the first layer has p-type conductivity, the second and third layers have type n-conductivity, the doping concentrations being of the order of 10 18 at/cm 3 and 10 16 at/cm 3 , respectively.
Claim 9
Dependent Claim
25 words
A diode as claimed in claim 1, wherein the layers are made of a compound corresponding to the formula Ga 1 -x Al x As.
References Cited (Backward Citations)
US3959646A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-07-18 | 1981-01-17 | 1981-07-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-18 | 1985-01-17 | 1985-07-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-18 | 1989-01-17 | 1989-07-19 | $7700.00 | Window Closed / Lapsed |