US4590507A
Expired / Lapsed
US
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Variable gap devices
Assignee: Nokia Bell Labs
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Filing: 1984-07-31
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Granted: 1986-05-20
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Expires: 2004-07-31
Abstract
Abstract A device having a selectively doped varying bandgap region with pyroelectric characteristics is described which is useful as a photodetector or temperature sensor. A plurality of selectively doped regions forming a superlattice may also be used. Ferroelectric devices are also described.
Inventors
- 👤 Federico Capasso
- 👤 Arthur C. Gossard
- 👤 Michael J. Stavola
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:31
CPC Classifications
H; H10; H10D; H10D62/00; H10D62/80; H10D62/81; H10D62/815; H10D62/8171; H10N; H10N15/00; H10N15/10; H10N15/15
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
60 words
A device comprising first and second semiconductor regions, first and second electrical contacts to said first and second regions, respectively, a third region between said first and second semiconductor regions, said third region comprising at least one graded bandgap region, a confining region adjacent said third region, said confining region and said third region forming a carrier confining energy well.
Claim 2
Independent Claim
60 words
A device comprising first and second semiconductor regions, first and second electrical contacts to said first and second regions, respectively, a third region between said first and second semiconductor regions, said third region comprising at least one graded bandgap region, a confining region adjacent said third region, said confining region and said third region forming a carrier confining energy well.
Claim 3
Dependent Claim
40 words
A device as recited in claim 1 in which said third region comprises a selectively doped region with the energy levels of the carriers and the dopant atoms being on different sides of the Fermi level at zero applied bias.
Claim 4
Dependent Claim
23 words
A device as recited in claim 2 in which said first and second contacts apply an electric field parallel to said third region.
Claim 5
Dependent Claim
23 words
A device as recited in claim 2 in which said first and second contacts apply an electric field perpendicular to said third region.
Claim 6
Dependent Claim
29 words
A device as recited in claim 2 further comprising an electrical contact to said third region, said contact applying an electric field perpendicular to said region of said superlattice.
Claim 7
Dependent Claim
19 words
A device as recited in claim 2 in which said first and second regions have the same conductivity type.
Claim 8
Dependent Claim
18 words
A device as recited in claim 2 in which said first and second regions have opposite conductivity type.
Claim 9
Dependent Claim
16 words
A device as recited in claim 2 in which said selectively doped region is doped n-type.
Claim 10
Dependent Claim
16 words
A device as recited in claim 2 in which said selectively doped region is doped p-type.
Claim 11
Dependent Claim
28 words
A device as recited in claim 2 in which said third region comprises a constant bandgap region and a varying bandgap region, said constant bandgap region being doped.
Claim 12
Dependent Claim
13 words
A device as recited in claim 10 in which said doping is n-type.
Claim 13
Dependent Claim
13 words
A device as recited in claim 10 in which said doping is p-type.
Claim 14
Dependent Claim
30 words
A device as recited in claim 11 in which said varying bandgap region has a local maximum in the conduction band above the Fermi level thereby forming two electron wells.
Claim 15
Dependent Claim
30 words
A device as recited in claim 13 in which said varying bandgap region comprises two local maxima in the conduction band above the Fermi level thereby forming two electron wells.
Claim 16
Dependent Claim
52 words
A device as recited in claim 2 in which said third region comprises a superlattice, said superlattice comprising a plurality of regions, said regions comprising a selectively doped region with the energy levels of the carriers and the dopant atoms being on different sides of the Fermi level at zero applied bias.
Claim 17
Dependent Claim
31 words
A device as recited in claim 15 in which said superlattice regions comprise a constant bandgap region and a varying bandgap region, said constant bandgap region being said selectively doped region.
Claim 18
Dependent Claim
29 words
A device as recited in claim 6 in which said varying bandgap regions have local maxima in the conduction band above the Fermi level thereby forming two electron wells.
Claim 19
Dependent Claim
30 words
A device as recited in claim 17 in which said varying bandgap regions comprise two local maxima in the conduction band above the Fermi level thereby forming three electron wells.
Claim 20
Dependent Claim
16 words
A device as recited in claim 15 further comprising an electrical contact to said superlattice region.
References Cited (Backward Citations)
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