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US5270225A
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Method of making a resonant tunneling semiconductor device
Assignee: NXP USA Inc
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Filing: 1992-02-21
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Granted: 1993-12-14
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Expires: 2012-02-21
Abstract
Abstract A resonant tunneling semiconductor device having two large bandgap barrier layers (12, 14) separated by a quantum well (13) is provided. The two barriers (12,14) and the quantum well (13) are formed between first and second semiconductor layers (11, 16) of a first conductivity type. A monolayer (17) of material having a different bandgap than the quantum well material is provided in the quantum well thereby lowering the ground state energy level of the quantum well. Alternatively, monolayers (18, 19) having a different bandgap than that of the first and second semiconductor layers (11, 16) are formed in the first and second semiconductor layers, respectively, outside of the quantum well (13).
Inventors
- 👤 Herbert Goronkin
- 👤 Jun Shen
- 👤 Saied Tehrani
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 04:45
CPC Classifications
B; B82; B82Y; B82Y10/00; B82Y30/00; H; H10; H10D; H10D10/00; H10D10/01; H10D10/021; H10D10/80; H10D10/821; H10D10/881; H10D62/00; H10D62/80; H10D62/85
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
117 words
A method of making a resonant tunneling semiconductor device comprising the steps of: providing a substrate on which a resonant tunneling semiconductor device can be formed; forming a first spacer layer having a top; forming a first monolayer in the first spacer layer a predetermined distance from the top of the first spacer layer; forming a first barrier layer covering the first spacer layer; forming a quantum well covering the first barrier layer; forming a second monolayer in a central portion of the quantum well; forming second barrier layer covering the quantum well; forming a second spacer layer; and forming a third monolayer in the second spacer layer at a predetermined distance from the second barrier layer.
Claim 2
Independent Claim
117 words
A method of making a resonant tunneling semiconductor device comprising the steps of: providing a substrate on which a resonant tunneling semiconductor device can be formed; forming a first spacer layer having a top; forming a first monolayer in the first spacer layer a predetermined distance from the top of the first spacer layer; forming a first barrier layer covering the first spacer layer; forming a quantum well covering the first barrier layer; forming a second monolayer in a central portion of the quantum well; forming second barrier layer covering the quantum well; forming a second spacer layer; and forming a third monolayer in the second spacer layer at a predetermined distance from the second barrier layer.
Claim 3
Dependent Claim
57 words
The method of claim 1 wherein the step of providing a substrate further comprises: providing a collector region of a first conductivity type; and forming a base region of a second conductivity type in the collector region, wherein the step of forming a first spacer layer includes forming the first spacer layer coupled to the base region.
Claim 4
Dependent Claim
32 words
The method of claim 2 wherein the step of forming a first spacer layer further comprises: doping at least a bottom portion of the first spacer layer to the first conductivity type.
Claim 5
Dependent Claim
29 words
The method of claim 9 wherein the step of forming a first monolayer includes forming the first monolayer approximately thirty angstroms from the top of the first spacer layer.
Claim 6
Dependent Claim
26 words
The method of claim 4 wherein the step of forming a second monolayer includes forming the second monolayer approximately thirty angstroms from the second spacer layer.
Claim 7
Independent Claim
139 words
A method for making a resonant tunneling device comprising the steps of: providing a substrate having a collector region of a first conductivity type and a base region of a second conductivity type in the collector region; and forming a resonant tunneling diode on top of the base region and electrically coupled to the base region, wherein the resonant tunneling diode includes a first spacer layer formed on the base region, wherein at least a bottom portion of the first spacer layer is doped to the first conductivity type; a quantum well formed on the first spacer layer; at least one monolayer formed at a central portion of the quantum well, wherein the at least one monolayer comprises a material having a higher bandgap energy than the quantum well; and forming a second spacer layer over the quantum well.
Claim 8
Independent Claim
139 words
A method for making a resonant tunneling device comprising the steps of: providing a substrate having a collector region of a first conductivity type and a base region of a second conductivity type in the collector region; and forming a resonant tunneling diode on top of the base region and electrically coupled to the base region, wherein the resonant tunneling diode includes a first spacer layer formed on the base region, wherein at least a bottom portion of the first spacer layer is doped to the first conductivity type; a quantum well formed on the first spacer layer; at least one monolayer formed at a central portion of the quantum well, wherein the at least one monolayer comprises a material having a higher bandgap energy than the quantum well; and forming a second spacer layer over the quantum well.
Claim 9
Dependent Claim
39 words
The method of claim 6 further comprising the steps of: forming an emitter electrode coupled to the second spacer layer; forming a base electrode coupled to the base region; and forming a collector electrode coupled to the collector region.
Claim 10
Dependent Claim
37 words
The method of claim 6 further comprising the step of forming at least one monolayer outside the quantum well in the first spacer layer comprising a material having a different bandgap energy than the first spacer layer.
Claim 11
Dependent Claim
37 words
The method of claim 8 further comprising the step of forming at least one monolayer outside the quantum well in the second spacer layer comprising a material having a different bandgap energy than the second spacer layer.
Claim 12
Dependent Claim
40 words
The method of claim 8 wherein the step of forming a quantum well further comprises forming a first and a second barrier layer of a wide bandgap material and forming narrow bandgap material between the first and second barrier layers.
Claim 13
Independent Claim
92 words
A method for making a resonant tunneling semiconductor device comprising the steps of: providing a substrate on which a resonant tunneling semiconductor device can be formed; forming a first spacer layer; forming a first barrier layer covering the first spacer layer; forming a quantum well covering the first barrier layer; forming a monolayer in a central portion of the quantum well, the monolayer having a higher bandgap energy than the quantum well; forming a second barrier layer covering the quantum well; and forming a second spacer layer over the second barrier layer.
Claim 14
Independent Claim
92 words
A method for making a resonant tunneling semiconductor device comprising the steps of: providing a substrate on which a resonant tunneling semiconductor device can be formed; forming a first spacer layer; forming a first barrier layer covering the first spacer layer; forming a quantum well covering the first barrier layer; forming a monolayer in a central portion of the quantum well, the monolayer having a higher bandgap energy than the quantum well; forming a second barrier layer covering the quantum well; and forming a second spacer layer over the second barrier layer.
Claim 15
Dependent Claim
11 words
The method of claim 11, wherein the monolayer comprises aluminum arsenide.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-12-13 | 1997-06-14 | 1997-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-12-13 | 2001-06-14 | 2001-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-12-13 | 2005-06-14 | 2005-12-14 | $7700.00 | Window Closed / Lapsed |