US4602352A
Expired / Lapsed
US
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Apparatus and method for detection of infrared radiation
Assignee: University of Pittsburgh
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Filing: 1984-04-17
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Granted: 1986-07-22
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Expires: 2004-04-17
Abstract
Abstract An infrared detector and method of detection based on depletion of charge stored in localized states is disclosed. The detector and method involve the determination of the depletion of charge stored in localized states at low temperatures caused by electric field-assisted photoemission of charge carriers from the localized states. The depletion of stored charge is indicative of the integrated incident flux of infrared radiation. The depletion of stored charge can be sensed by quantum mechanical field ionization, field detachment or otherwise.
Inventors
- 👤 Darryl D. Coon
- 👤 Gustav E. Derkits, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:08
CPC Classifications
G; G01; G01J; G01J5/00; G01J5/10; G01J5/34; G11; G11C; G11C11/00; G11C11/21; G11C11/22; G11C7/00; G11C7/005; H; H10; H10F; H10F39/00; H10F39/10; H10F39/107; H10F39/12
Claims Analysis
Total Claims: 40
Claim 1
Independent Claim
82 words
A method of detection of electromagnetic radiation comprising: (a) storing of charge in localized states in a semiconductor; (b) maintaining the temperature of said semiconductor sufficiently low to avoid appreciable thermal excitation of charge carriers out of said localized states; (c) applying a first electric field to said localized states; (d) exposing the semiconductor to electromagnetic radiation having sufficient energy to cause photoemission of charge from said localized states; and (e) determining the extent of depletion of charge caused by said photoemission.
Claim 2
Independent Claim
82 words
A method of detection of electromagnetic radiation comprising: (a) storing of charge in localized states in a semiconductor; (b) maintaining the temperature of said semiconductor sufficiently low to avoid appreciable thermal excitation of charge carriers out of said localized states; (c) applying a first electric field to said localized states; (d) exposing the semiconductor to electromagnetic radiation having sufficient energy to cause photoemission of charge from said localized states; and (e) determining the extent of depletion of charge caused by said photoemission.
Claim 3
Dependent Claim
22 words
A method according to claim 1 including storing of charge in localized states which comprise conduction band electrons bound to charged impurities.
Claim 4
Dependent Claim
22 words
A method according to claim 1 including storing of charge in localized states which comprise conduction band electrons bound to neutral impurities.
Claim 5
Dependent Claim
22 words
A method according to claim 1 including storing of charge in localized states which comprise valence band holes bound to charged impurities.
Claim 6
Dependent Claim
22 words
A method according to claim 1 including storing of charge in localized states which comprise valence band holes bound to neutral impurities.
Claim 7
Dependent Claim
26 words
A method according to claim 1 including storing of charge in localized states which comprise conduction band electrons and valence band holes bound to charged impurities.
Claim 8
Dependent Claim
26 words
A method according to claim 1 including storing of charge in localized states which comprise conduction band electrons and valence band holes bound to neutral impurities.
Claim 9
Dependent Claim
31 words
A method according to claim 1 including storing of charge in localized states of a semiconductor which is selected from the group consisting of silicon, germanium, gallium arsenide and semiconductor alloys.
Claim 10
Dependent Claim
60 words
A method according to claim 1 wherein determining the depletion of charge stored in localized states is accomplished by applying a second electric field to said localized states having a strength greater than said first field and sufficient to cause the release of charge remaining in the localized states after exposure to said radiation and by measuring the released charge.
Claim 11
Dependent Claim
14 words
A method according to claim 9 wherein the releasing of charge comprises field ionization.
Claim 12
Dependent Claim
33 words
A method according to claim 1 wherein determining the depletion charge stored in localized states is accomplished by measuring the electric field associated with the space charge due to ionization of localized states.
Claim 13
Dependent Claim
37 words
A method according to claim 1 wherein determining the depletion of charge stored in localized states is accomplished by measuring the charge required to repopulate the localized states from which charge has been released during said photoemission.
Claim 14
Dependent Claim
39 words
A method according to claim 1 wherein storing of charge in localized states is accomplished by injecting charge carriers from at least one electrical contact into said semiconductor whereby said charge carriers are captured and trapped in localized states.
Claim 15
Dependent Claim
33 words
A method according to claim 13 wherein storing of charge in localized states is accomplished by injecting charge carriers from an electrical contact comprised of a heavily doped n-type region of said semiconductor.
Claim 16
Dependent Claim
33 words
A method according to claim 13 wherein storing the charge in localized states is accomplished by injecting charge carriers from an electrical contact comprised of a heavily doped p-type region of said semiconductor.
Claim 17
Dependent Claim
38 words
A method according to claim 13 wherein storing of charge in localized states is accomplished by injecting charge carriers from electrical contacts comprised of a heavily doped n-type region and a heavily doped p-type region of said semiconductor.
Claim 18
Dependent Claim
26 words
A method according to claim 1 wherein applying said first electric field is accomplished by providing a potential difference between electrical contacts provided on said semiconductor.
Claim 19
Dependent Claim
26 words
A method according to claim 1 further comprising altering the strength of said first electric field to vary the range of photon energies which are detected.
Claim 20
Dependent Claim
98 words
A detector of electromagnetic radiation comprising: (a) a semiconductor having localized states therein; (b) means for storage of charge in said localized states in the semiconductor; (c) means for maintaining the temperature of said semiconductor sufficiently low to avoid appreciable thermal excitation of charge carriers out of said localized states; (d) means for applying a first electric field to said localized states; (e) means for exposing the semiconductor to electromagnetic radiation having sufficient energy to cause photoemission of charge from said localized states; and (f) means for determining the extent of depletion of charge caused by said photoemission.
Claim 21
Dependent Claim
98 words
A detector of electromagnetic radiation comprising: (a) a semiconductor having localized states therein; (b) means for storage of charge in said localized states in the semiconductor; (c) means for maintaining the temperature of said semiconductor sufficiently low to avoid appreciable thermal excitation of charge carriers out of said localized states; (d) means for applying a first electric field to said localized states; (e) means for exposing the semiconductor to electromagnetic radiation having sufficient energy to cause photoemission of charge from said localized states; and (f) means for determining the extent of depletion of charge caused by said photoemission.
Claim 22
Dependent Claim
18 words
A detector according to claim 19 wherein said localized states comprise conduction band electrons bound to charged impurities.
Claim 23
Dependent Claim
18 words
A detector according to claim 19 wherein said localized states comprise conduction band electrons bound to neutral impurities.
Claim 24
Dependent Claim
18 words
A detector according to claim 19 wherein said localized states comprise valence band holes bound to charged impurities.
Claim 25
Dependent Claim
18 words
A detector according to claim 19 wherein said localized states comprise valence band holes bound to neutral impurities.
Claim 26
Dependent Claim
22 words
A detector according to claim 19 wherein said localized states comprise conduction band electrons and valence band holes bound to charged impurities.
Claim 27
Dependent Claim
22 words
A detector according to claim 19 wherein said localized states comprise conduction band electrons and valence band holes bound to neutral impurities.
Claim 28
Dependent Claim
23 words
A detector according to claim 19 wherein said semicondutor is selected from the group consisting of silicon, germanium, gallium arsenide and semiconductor alloys.
Claim 29
Dependent Claim
58 words
A detector according to claim 19 wherein said means for determining the depletion of charge stored in localized states further comprises: (a) means for applying an electric field to the localized states having sufficient strength to cause the release of charge from the localized states after exposure to said radiation; and (b) means for measuring the released charge.
Claim 30
Dependent Claim
18 words
A detector according to claim 27 wherein said means for applying an electric field includes field ionization means.
Claim 31
Dependent Claim
38 words
A detector according to claim 19 wherein said means for determining the depletion of charge stored in localized states further comprises means for measuring the electric field associated with the space charge due to ionization of localized states.
Claim 32
Dependent Claim
39 words
A detector according to claim 19 wherein said means for determining the depletion of charge stored in localized states further comprises measurement of charge required to repopulate the localized states from which charge has been released during field-assisted photoemission.
Claim 33
Dependent Claim
42 words
A detector according to claim 19 wherein said means for storage of charge in localized states further comprises injection of charge carriers from at least one electrical contact into said semiconductor whereby said charge carriers are captured and trapped in localized states.
Claim 34
Dependent Claim
21 words
A detector according to claim 31 wherein said electrical contact is comprised of a heavily doped n-type region of said semiconductor.
Claim 35
Dependent Claim
21 words
A detector according to claim 31 wherein said electrical contact is comprised of a heavily doped p-type region of said semiconductor.
Claim 36
Dependent Claim
27 words
A detector according to claim 31 wherein said electrical contacts are comprised of a heavily doped n-type region and a heavily doped p-type region of said semiconductor.
Claim 37
Dependent Claim
29 words
A detector according to claim 19 wherein said means for applying an electric field further comprises means for maintaining a potential difference between electric contacts provided on said semiconductor.
Claim 38
Dependent Claim
25 words
A detector according to claim 19 including means for changing the range of detectable photon energies by altering the strength of said first electric field.
Claim 39
Dependent Claim
19 words
A detector according to claim 19 wherein said localized states are impurities in the i-region of a p-i-n diode.
Claim 40
Dependent Claim
23 words
An infrared detection system wherein a plurality of detectors as described in claim 19 are provided as an array on a semiconductor wafer.
References Cited (Backward Citations)
US2677714A
Cited
US3398316A
Cited
US3182198A
Cited
US3341825A
Cited
US3652270A
Cited
US4085456A
Cited
US3786441A
Cited
US3904911A
Cited
US3801820A
Cited
US4107564A
Cited
US4225222A
Cited
US4265991A
Cited
US4356246A
Cited
US4241421A
Cited
US4349617A
Cited
US4359512A
Cited
US4359514A
Cited
US4394426A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-07-21 | 1990-01-20 | 1990-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-07-21 | 1994-01-20 | 1994-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-07-21 | 1998-01-20 | 1998-07-22 | $7700.00 | Window Closed / Lapsed |