Patent US6515316B1 successfully refreshed from Google Patents.
US6515316B1
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Partially relaxed channel HEMT device
Assignee: Northrop Grumman Systems Corp
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Filing: 2000-07-14
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Granted: 2003-02-04
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Expires: 2020-07-14
Abstract
Abstract A HEMT device comprises a buffer layer disposed over a substrate. A partially-relaxed channel is disposed over the buffer layer and a barrier layer is disposed over the channel. A cap layer is disposed over the barrier layer and a gate is positioned on the barrier layer. A source and a drain are positioned on the barrier layer on opposite sides of the gate.
Inventors
- 👤 Michael Wojtowicz
- 👤 Tsung-Pei Chin
- 👤 Michael E. Barsky
- 👤 Ronald W. Grundbacher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:54
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/40; H10D30/47; H10D30/471; H10D30/473; H10D62/00; H10D62/80; H10D62/85; H10D62/8503
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
95 words
An InP high electron mobility transistor (HEMT) device having a frequency response comprising: buffer layer disposed over a substrate; a partially-relaxed channel disposed over said buffer layer to a sufficient thickness so that dislocations form in the channel in more than one direction; a cap layer disposed over said barrier layer; a gate positioned on said barrier layer; and a source and a drain positioned on said cap layer, wherein said frequency response of said HEMT device is improved when compared to a HEMT device having a channel with dislocations in only a single direction.
Claim 2
Dependent Claim
95 words
An InP high electron mobility transistor (HEMT) device having a frequency response comprising: buffer layer disposed over a substrate; a partially-relaxed channel disposed over said buffer layer to a sufficient thickness so that dislocations form in the channel in more than one direction; a cap layer disposed over said barrier layer; a gate positioned on said barrier layer; and a source and a drain positioned on said cap layer, wherein said frequency response of said HEMT device is improved when compared to a HEMT device having a channel with dislocations in only a single direction.
Claim 3
Dependent Claim
17 words
A HEMT device as in claim 1 , further comprising a doping layer disposed on said channel.
Claim 4
Dependent Claim
110 words
An InP high electron mobility transistor (HEMT) device having a frequency response comprising: a buffer layer disposed over a substrate; a partially-relaxed channel disposed over said buffer layer fabricated of a material which when disposed to a first thickness is pseudomorphic and when disposed of a second thickness is fully relaxed, said channel having a thickness intermediate said first and second thicknesses and being of a sufficient thickness so that dislocations form in more than one direction; a barrier layer disposed over said channel; a cap layer disposed over said barrier layer; a gate positioned on said barrier layer; and a source and a drain positioned on said cap layer.
Claim 5
Dependent Claim
110 words
An InP high electron mobility transistor (HEMT) device having a frequency response comprising: a buffer layer disposed over a substrate; a partially-relaxed channel disposed over said buffer layer fabricated of a material which when disposed to a first thickness is pseudomorphic and when disposed of a second thickness is fully relaxed, said channel having a thickness intermediate said first and second thicknesses and being of a sufficient thickness so that dislocations form in more than one direction; a barrier layer disposed over said channel; a cap layer disposed over said barrier layer; a gate positioned on said barrier layer; and a source and a drain positioned on said cap layer.
Claim 6
Dependent Claim
15 words
A HEMT device as in claim 3 , wherein said channel comprises an InGaAs material.
Claim 7
Dependent Claim
16 words
A HEMT device as in claim 4 , wherein said InGaAs material comprises approximately 75% In.
Claim 8
Dependent Claim
143 words
An InP high electron mobility transistor (HEMT) device having a frequency response comprising: a buffer layer disposed over a substrate; a partially-relaxed channel disposed over said buffer layer, said partially relaxed channel comprising a material having a lattice constant, said buffer layer comprising a material having a lattice constant different than the lattice constant of the channel material, said partially-relaxed channel fabricated of a material which when disposed to a first thickness is pseudomorphic and when disposed of a second thickness is fully relaxed, said channel having a thickness intermediate said first and second thickness and being of a sufficient thickness so that dislocations form in more than one direction; a barrier layer disposed over said channel; a cap layer disposed over said barrier layer; a gate positioned on said barrier layer; and a source and a drain positioned on said cap layer.
Claim 9
Dependent Claim
143 words
An InP high electron mobility transistor (HEMT) device having a frequency response comprising: a buffer layer disposed over a substrate; a partially-relaxed channel disposed over said buffer layer, said partially relaxed channel comprising a material having a lattice constant, said buffer layer comprising a material having a lattice constant different than the lattice constant of the channel material, said partially-relaxed channel fabricated of a material which when disposed to a first thickness is pseudomorphic and when disposed of a second thickness is fully relaxed, said channel having a thickness intermediate said first and second thickness and being of a sufficient thickness so that dislocations form in more than one direction; a barrier layer disposed over said channel; a cap layer disposed over said barrier layer; a gate positioned on said barrier layer; and a source and a drain positioned on said cap layer.
Claim 10
Dependent Claim
17 words
A HEMT device as in claim 6 , wherein said partially relaxed channel comprises an InGaAs material.
Claim 11
Dependent Claim
17 words
A HEMT device as in claim 7 , wherein said partially relaxed channel comprises substantially 75% In.
Claim 12
Dependent Claim
144 words
An InP high electron mobility transistor (HEMT) device having a frequency response comprising: a buffer layer disposed over a substrate; a partially-relaxed channel disposed over said buffer layer, said partially relaxed channel comprising a composite GaAs/InGaAs material and having a lattice constant, said buffer layer comprising a material having a lattice constant different than the lattice constant of the channel material, said partially-relaxed channel fabricated of a material which when disposed to a first thickness is pseudomorphic and when disposed of a second thickness is fully relaxed, said channel comprising a composite GaAs/InGaAs material having a thickness between approximately 22 and 30 nanometers which is intermediate said first and second thickness; a barrier layer disposed over said channel; a cap layer disposed over said barrier layer; a gate positioned on said barrier layer; and a source and a drain positioned on said cap layer.
Claim 13
Dependent Claim
144 words
An InP high electron mobility transistor (HEMT) device having a frequency response comprising: a buffer layer disposed over a substrate; a partially-relaxed channel disposed over said buffer layer, said partially relaxed channel comprising a composite GaAs/InGaAs material and having a lattice constant, said buffer layer comprising a material having a lattice constant different than the lattice constant of the channel material, said partially-relaxed channel fabricated of a material which when disposed to a first thickness is pseudomorphic and when disposed of a second thickness is fully relaxed, said channel comprising a composite GaAs/InGaAs material having a thickness between approximately 22 and 30 nanometers which is intermediate said first and second thickness; a barrier layer disposed over said channel; a cap layer disposed over said barrier layer; a gate positioned on said barrier layer; and a source and a drain positioned on said cap layer.
References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 2006-02-03 | 2006-08-05 | 2007-02-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2010-02-03 | 2010-08-05 | 2011-02-04 | $3760.00 | Window Closed / Lapsed |
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