Patent EP0186460A2 successfully refreshed from Google Patents.
EP0186460A2
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Semiconductor photodetector
Assignee: Fujitsu Ltd
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Filing: 1985-12-20
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Granted: —
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Expires: 2005-12-20
Abstract
Abstract A semiconductor photodetector, such as a PIN photodiode or an avalanche photodiode, comprising an InP substrate (1,21), a first InP layer (2, 22), a GaInAs or GaInAsP light absorbing layer (3, 23), and a second InP layer (4; 25, 26). All of the layers are successively grown by a vapor phase epitaxial process wherein the lattice constant of the GaInAs (GalnAsP) layer (3, 23) is larger than that of the first InP layer (2, 22) at room temperature. Consequently the photodetector has a low dark current.
Inventors
- 👤 Shuzo Kagawa
- 👤 Junji Komeno
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 15:22
CPC Classifications
H; H10; H10F; H10F77/00; H10F77/10; H10F77/12; H10F77/124; H10F77/1248; H10F30/00; H10F30/20; H10F30/21; H10F30/22; H10F30/223; H10F30/225; Y; Y02; Y02E; Y02E10/00; Y02E10/50; Y02E10/544; Y10; Y10S; Y10S148/00; Y10S148/015; Y10S148/072; Y10S148/097; Y10S148/12
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
58 words
A semiconductor photodetector comprising an InP substrate, a first InP layer, a GaInAs (or GalnAsP) layer, and a second InP layer, which layers are successively epitaxially formed by a vapor phase epitaxial process on said InP substrate, a lattice constant of said GaInAs (or GaInAsP) layer being larger than that of said first InP layer at room temperature.
Claim 2
Dependent Claim
58 words
A semiconductor photodetector comprising an InP substrate, a first InP layer, a GaInAs (or GalnAsP) layer, and a second InP layer, which layers are successively epitaxially formed by a vapor phase epitaxial process on said InP substrate, a lattice constant of said GaInAs (or GaInAsP) layer being larger than that of said first InP layer at room temperature.
Claim 3
Dependent Claim
33 words
A semiconductor photodetector according to claim 1, wherein a lattice mismatching degree (Δa/a) between said GaInAs (or GaInAsP) layer and said first InP layer is within the range: over 0 to 0.2%; wherein:
Claim 4
Dependent Claim
24 words
A semiconductor photodetector according to claim 1 or 2, wherein said GaInAs (or GaInAsP) layer has a thickness of from 1 to 2 µm.
Claim 5
Dependent Claim
52 words
A semiconductor photodetector according to claim 1, 2, or 3, wherein said first InP layer is an undoped N -type layer, said GaInAs (or GaInAsP) layer is an undoped N - -type layer, and said second InP layer is an N-type layer, in which second InP layer a P-type region is formed.
Claim 6
Dependent Claim
62 words
A semiconductor photodetector comprising an InP substrate (1), (a) first InP layer (2), a GaInAsP layer (3), and a second InP layer (4), which layers are successively epitaxially formed by a vapor phase epitaxial process on said InP substrate (1), a lattice constant of said G aInAsP layer (3) being larger than that of said first InP layer (2) at room temperature.
Claim 7
Dependent Claim
62 words
A semiconductor photodetector comprising an InP substrate (1), (a) first InP layer (2), a GaInAsP layer (3), and a second InP layer (4), which layers are successively epitaxially formed by a vapor phase epitaxial process on said InP substrate (1), a lattice constant of said G aInAsP layer (3) being larger than that of said first InP layer (2) at room temperature.
Claim 8
Dependent Claim
33 words
A semiconductor photodetector according to claim 5, wherein the lattice mismatching degree (Aa/a) between said GaInAsP layer (3) and said first InP layer (2) is within the rage: over 0 to 0.2%; wherein:
Claim 9
Dependent Claim
24 words
A semiconductor photodetector according to claim 5 or 6, wherein said G aInAsP layer (3) has a thickness of from 1 to 2 µm.
Claim 10
Dependent Claim
55 words
A semiconductor photodetector according to claim 5, 6, or 7, wherein said first InP layer (2) is an undoped N - -type layer, said GaInAsP layer (3) is an undoped N -type layer, and said second InP layer (4) is an N-type layer, in which second InP layer (4) a P-type region (6) is formed.
Claim 11
Dependent Claim
92 words
A semiconductor photodetector comprising an InP substrate (21), a first InP layer (22), a GaInAs layer (23), a GaInAsP layer (24), and a second InP layer, which layers are successively epitaxially formed by a vapor phase epitaxial process on said InP substrate (21), a lattice constant of said GaInAs layer (23) being larger than that of said first InP layer (22) at room temperature and a lattice constant of said GaInAsP layer (24) lying in the range between said InP layer (22) lattice constant and said GaInAs layer (23) lattice constant, inclusively.
Claim 12
Dependent Claim
92 words
A semiconductor photodetector comprising an InP substrate (21), a first InP layer (22), a GaInAs layer (23), a GaInAsP layer (24), and a second InP layer, which layers are successively epitaxially formed by a vapor phase epitaxial process on said InP substrate (21), a lattice constant of said GaInAs layer (23) being larger than that of said first InP layer (22) at room temperature and a lattice constant of said GaInAsP layer (24) lying in the range between said InP layer (22) lattice constant and said GaInAs layer (23) lattice constant, inclusively.
Claim 13
Dependent Claim
32 words
A semiconductor photodetector according to claim 9, wherein the lattice mismatching degree (Aa/a) between said GaInAs layer (23) and said first InP within the range: layer (22) is/over 0 to 0.2%; wherein:
Claim 14
Dependent Claim
62 words
A semiconductor photodetector according to claim 9, or 10, wherein said first InP layer (22) is an N-type layer, said GaInAs layer (23) is an undoped N -type layer, said GaInAsP layer (24) is an undoped N - -type layer, and said second InP layer (25, 26) is an N-type layer, in which second InP layer a P-type region (28) is formed.
Claim 15
Dependent Claim
25 words
A semiconductor photodetector according to claim 11, wherein another undoped GaInAsP layer is formed between said first InP layer (22) and said InGaAs layer (23).
References Cited (Backward Citations)
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