Patent EP0345972A1 successfully refreshed from Google Patents.
EP0345972A1
Expired / Lapsed
EP
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Quantum-well radiation detector
Assignee: AT&T Inc
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Filing: 1989-05-25
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Granted: —
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Expires: 2009-05-25
Abstract
Abstract Electromagnetic radiation such as, in particular, infrared radiation is detected opto-electronically by means of a superlattice structure forming quantum wells (21) having a single bound state (24,) in the interest of minimizing dark-current, relatively wide barriers (22) are used between quantum wells. Resulting highly sensitive, high-speed detectors can be used in optical communications, for terrain mapping, and for infrared viewing.
Inventors
- 👤 Clyde George Bethea
- 👤 Barry Franklin Levine
- 👤 Roger John Malik
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 18:49
CPC Classifications
H; H10; H10F; H10F77/00; H10F77/10; H10F77/14; H10F77/146; B; B82; B82Y; B82Y20/00; H10F39/00; H10F39/10; H10F39/12; H10F39/15; H10F39/151; H10F39/156; H10F39/157; H10W; H10W90/00; H10W72/00; H10W72/071; H10W72/075; H10W72/07551; H10W72/07554; H10W72/50; H10W72/531; H10W72/536; H10W72/541; H10W72/547; H10W72/851; H10W72/874; H10W72/884
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
129 words
A device comprising a detector for producing an electrical effect in response to incident electromagnetic radiation at a wavelength of interest, said detector comprising a substrate-supported semiconductor superlattice (13) between contact layers (12, 14), said superlattice comprising interleaved quantum-well (21) and barrier layers (22), quantum wells formed by said layers having one bound energy state (24) which is either a valence-band bound energy state or a conduction-band bound energy state, said quantum wells being adapted for carrier excitation by said radiation, excitation being either from said valence-band bound energy state into a valence-band continuum energy state or else from said conduction-band bound energy state into a conduction-band continuum energy state, CHARACTERISED IN THAT the thickness of said barrier layers is significantly greater than the thickness of said quantum-well layers.
Claim 2
Independent Claim
129 words
A device comprising a detector for producing an electrical effect in response to incident electromagnetic radiation at a wavelength of interest, said detector comprising a substrate-supported semiconductor superlattice (13) between contact layers (12, 14), said superlattice comprising interleaved quantum-well (21) and barrier layers (22), quantum wells formed by said layers having one bound energy state (24) which is either a valence-band bound energy state or a conduction-band bound energy state, said quantum wells being adapted for carrier excitation by said radiation, excitation being either from said valence-band bound energy state into a valence-band continuum energy state or else from said conduction-band bound energy state into a conduction-band continuum energy state, CHARACTERISED IN THAT the thickness of said barrier layers is significantly greater than the thickness of said quantum-well layers.
Claim 3
Dependent Claim
27 words
A device as claimed in claim 1, the thickness of said barrier layers being greater than or equal to three times the thickness of said quantum-well layers.
Claim 4
Dependent Claim
20 words
A device as claimed in claim 1 or claim 2, said wavelength being greater than or equal to 3 µm.
Claim 5
Dependent Claim
18 words
A device as claimed in claim 3, said wavelength being in the range from 3 to 15 µm.
Claim 6
Independent Claim
18 words
A device as claimed in any of the preceding claims, said superlattice comprising interleaved layers of different materials.
Claim 7
Dependent Claim
20 words
A device as claimed in claim 5, said superlattice comprising Group IV semiconductor materials, and said quantum-well layers being p-doped.
Claim 8
Dependent Claim
16 words
A device as claimed in claim 6, said detector being monolithically integrated with silicon semiconductor devices.
Claim 9
Dependent Claim
20 words
A device as claimed in claim 5, said superlattice comprising Group III-V semiconductor materials, and said quantum-well layers being n-doped.
Claim 10
Dependent Claim
17 words
A device as claimed in claim 8, said detector being monolithically integrated with gallium arsenide semiconductor devices.
Claim 11
Independent Claim
36 words
A device as claimed in any of the preceding claims, said device comprising a plurality of said detectors forming a stack (12, 72, 73, 71, 14), said detectors being responsive to different respective wavelengths of interest.
References Cited (Backward Citations)
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