US4553155A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High speed bias-free photodetector
Assignee: Nokia Bell Labs
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Filing: 1984-03-22
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Granted: 1985-11-12
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Expires: 2004-03-22
Abstract
Abstract A high speed bias-free photodetector which capacitively couples the output signal to an external circuit is described.
Inventors
- 👤 Chung Y. Chen
- 👤 Alfred Y. Cho
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 05:03
CPC Classifications
H; H10; H10F; H10F77/00; H10F77/10; H10F77/12; H10F77/124; H10F77/1248; H10F30/00; H10F30/20; H10F30/21; H10F30/22; H10F30/221; H10F30/2215; Y; Y02; Y02E; Y02E10/00; Y02E10/50; Y02E10/544
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
75 words
A photodetector comprising: a first layer comprising a first semiconductor having a first conductivity type; a second layer comprising a second semiconductor having a second conductivity type; a semi-insulating substrate; said first and second layers forming a p-n junction and being disposed on said substrate; the first of said layers having a first electrode for connection to an external electrical circuit; and a second electrode on said substrate for connection to an external electrical circuit.
Claim 2
Dependent Claim
75 words
A photodetector comprising: a first layer comprising a first semiconductor having a first conductivity type; a second layer comprising a second semiconductor having a second conductivity type; a semi-insulating substrate; said first and second layers forming a p-n junction and being disposed on said substrate; the first of said layers having a first electrode for connection to an external electrical circuit; and a second electrode on said substrate for connection to an external electrical circuit.
Claim 3
Dependent Claim
20 words
A photodetector as recited in claim 1 in which said semi-insulating substrate has a resistivity greater than 10 7 Ωcm.
Claim 4
Dependent Claim
20 words
A photodetector as recited in claim 2 in which said second electrode comprises an electrically conducting layer contacting said substrate.
Claim 5
Dependent Claim
27 words
A photodetector as recited in claim 3 further comprising a third electrode contacting said first layer, said third electrode being electrically connected to said electrically conducting layer.
Claim 6
Dependent Claim
31 words
A photodetector as recited in claim 4 further comprising a third epitaxial layer, said third layer having a second conductivity type and being between and contacting said first and second layers.
Claim 7
Dependent Claim
24 words
A photodetector as recited in claim 5 in which the interface between said second and third layers is inverted and an inversion layer forms.
Claim 8
Dependent Claim
23 words
A photodetector as recited in claim 6 in which at least one of said first and third electrodes electrically contacts said inversion layer.
Claim 9
Dependent Claim
20 words
A photodetector as recited in claim 2, 4, 5, or 7 in which said substrate comprises a Group III-V compound.
Claim 10
Dependent Claim
21 words
A photodetector as recited in claim 8 in which said compound is selected from the group consisting of InP and GaAs.
Claim 11
Dependent Claim
15 words
A photodetector as recited in claim 8 in which said first conductivity type is n-type.
Claim 12
Dependent Claim
17 words
A photodetector as recited in claim 10 in which said first layer comprises a Group III-V compound.
Claim 13
Dependent Claim
32 words
A photodetector as recited in claim 11 in which said compound is selected from the group consisting of In x Ga 1-x As y P 1-y and Al x Ga 1-x As.
Claim 14
Dependent Claim
18 words
A photodetector as recited in claim 12 in which said second layer comprises Al x Ga 1-x As.
Claim 15
Dependent Claim
31 words
A photodetector as recited in claim 13 further comprising a third epitaxial layer comprising a third semiconductor having a second conductivity type, said third layer being disposed on said second layer.
Claim 16
Dependent Claim
16 words
A photodetector as recited in claim 2 in which said substrate comprises a Group II-VI compound.
Claim 17
Dependent Claim
18 words
A photodetector as recited in claim 15 in which said first and second layers comprise Group II-VI compounds.
Claim 18
Dependent Claim
18 words
A photodetector as recited in claim 2 in which said first and second layers comprise Group III-V compounds.
References Cited (Backward Citations)
US4075651A
Cited
US4173764A
Cited
US4194935A
Cited
US4258375A
Cited
US4257055A
Cited
US4314858A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-11-11 | 1989-05-13 | 1989-11-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-11-11 | 1993-05-13 | 1993-11-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-11-11 | 1997-05-13 | 1997-11-12 | $7700.00 | Window Closed / Lapsed |