Patent US6307221B1 successfully refreshed from Google Patents.
US6307221B1
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InxGa1-xP etch stop layer for double recess pseudomorphic high electron mobility transistor structures
Assignee: MACOM Technology Solutions Holdings Inc
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Filing: 1998-11-18
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Granted: 2001-10-23
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Expires: 2018-11-18
Abstract
Abstract The invention is a Pseudomorphic transistor structure having a semiconductor layer having a 2DEG layer therein, a Schottky layer, a transition layer and an ohmic contact layer on the transition layer, wherein a double recess structure is disposed through the ohmic layer onto the transition layer in which one or two layers of In y Ga 1−y P are used as etch-stop layers to define the depth of the recess.
Inventors
- 👤 David Danzilio
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 20:22
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/015; H10D30/40; H10D30/47; H10D30/471; H10D30/475; H10D30/4755
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
64 words
A Pseudomorphic HEMT structure, comprising: a semiconductor layer having a 2DEG layer therein; a layer of silicon atoms; a Schottky layer; a transition layer and an ohmic contact layer on said transition layer; a double recess structure disposed through said ohmic layer and into said transition layer; and an etch-stop layer of In x Ga 1−x P defining a bottom surface of said recess.
Claim 2
Dependent Claim
64 words
A Pseudomorphic HEMT structure, comprising: a semiconductor layer having a 2DEG layer therein; a layer of silicon atoms; a Schottky layer; a transition layer and an ohmic contact layer on said transition layer; a double recess structure disposed through said ohmic layer and into said transition layer; and an etch-stop layer of In x Ga 1−x P defining a bottom surface of said recess.
Claim 3
Dependent Claim
45 words
A Pseudomorphic HEMT as recited in claim 1 , wherein said double recess further comprises a first recess and a second recess, said first recess having a lower surface at a first depth and said second recess having said bottom surface at a second depth.
Claim 4
Dependent Claim
28 words
A Pseudomorphic HEMT as recited in claim 2 , wherein said first depth and said second depth are at a prescribed distance apart, said distance being ≧100 angstroms.
Claim 5
Dependent Claim
23 words
A Pseudomorphic HEMT as recited in claim 1 , wherein said semiconductor layer having said 2DEG layer therein is an InGaAs channel layer.
Claim 6
Dependent Claim
11 words
A Pseudomorphic HEMT as recited in claim 1 , wherein 0.4≧x≧0.6.
Claim 7
Dependent Claim
22 words
A Pseudomorphic HEMT as recited in claim 1 , wherein said transition layer is GaAs and said ohmic contact layer is AlGaAs.
Claim 8
Dependent Claim
123 words
A Pseudomorphic HEMT structure, comprising: a substrate having a buffer layer and a super lattice layer disposed thereon; a channel layer disposed on said super lattice layer; a spacer layer disposed on said channel layer; a Schottky layer disposed on said spacer layer, a transition layer over said Schottky layer, and an ohmic contact layer disposed on said transition layer; and a double recess structure through said ohmic layer and into said transition layer, said double recess having a first recess at a first depth d 1 , said second recess having a bottom surface at a second depth d 2 , said bottom surface being an etch-stop layer of In x Ga 1−x P between said Schottky layer and said transition layer.
Claim 9
Dependent Claim
123 words
A Pseudomorphic HEMT structure, comprising: a substrate having a buffer layer and a super lattice layer disposed thereon; a channel layer disposed on said super lattice layer; a spacer layer disposed on said channel layer; a Schottky layer disposed on said spacer layer, a transition layer over said Schottky layer, and an ohmic contact layer disposed on said transition layer; and a double recess structure through said ohmic layer and into said transition layer, said double recess having a first recess at a first depth d 1 , said second recess having a bottom surface at a second depth d 2 , said bottom surface being an etch-stop layer of In x Ga 1−x P between said Schottky layer and said transition layer.
Claim 10
Dependent Claim
28 words
A Pseudomorphic HEMT as recited in claim 7 , wherein another etch-stop layer of In x Ga 1−x P is disposed at said first depth, d 1 .
Claim 11
Dependent Claim
18 words
A Pseudomorphic HEMT as recited in claim 7 , wherein d 2 −d 1 =ΔD 2−1 ≧100 angstroms.
Claim 12
Dependent Claim
50 words
A Pseudomorphic HEMT as recited in claim 7 , wherein said substrate is GaAs, said buffer is GaAs, said super lattice is alternating layers of AlGaAs and GaAs, said channel layer is In y Ga 1−y As, said Schottky layer is n AlGaAs and said ohmic layer is n GaAs.
Claim 13
Dependent Claim
15 words
A Pseudomorphic HEMT as recited in claim 10 , wherein 0.1≧y≧0.25 for said channel layer.
Claim 14
Dependent Claim
148 words
A Pseudomorphic HEMT structure, comprising: a substrate having a buffer layer disposed thereon, a super lattice layer disposed on said buffer layer, a channel layer disposed on said super lattice layer, a spacer layer, a layer of silicon atoms disposed on said spacer layer, a Schottky layer, a transition layer disposed over said Schottky layer, and an ohmic contact layer disposed on said transition layer; a double recess disposed through said ohmic layer and said transition layer, said double recess having a first recess at a first depth d 1 , an etch-stop layer of In x Ga 1−x P disposed at said first depth d 1 , and said etch-stop layer having an opening therein; and said double recess having a second recess at a second depth d 2 , said second recess having a bottom surface of a second layer of In x Ga 1−x P.
Claim 15
Dependent Claim
148 words
A Pseudomorphic HEMT structure, comprising: a substrate having a buffer layer disposed thereon, a super lattice layer disposed on said buffer layer, a channel layer disposed on said super lattice layer, a spacer layer, a layer of silicon atoms disposed on said spacer layer, a Schottky layer, a transition layer disposed over said Schottky layer, and an ohmic contact layer disposed on said transition layer; a double recess disposed through said ohmic layer and said transition layer, said double recess having a first recess at a first depth d 1 , an etch-stop layer of In x Ga 1−x P disposed at said first depth d 1 , and said etch-stop layer having an opening therein; and said double recess having a second recess at a second depth d 2 , said second recess having a bottom surface of a second layer of In x Ga 1−x P.
Claim 16
Dependent Claim
18 words
A Pseudomorphic HEMT as recited in claim 12 , wherein d 2 −d 1 ΔD 2 ≧100 angstroms.
Claim 17
Dependent Claim
46 words
A Pseudomorphic HEMT as recited in claim 12 , wherein said substrate is GaAs, said buffer is GaAs, said supperlattice is AlGaAs/GaAs, said channel layer is In y Ga 1−y As, said Schottky layer is n − AlGaAs and said ohmic layer is n − GaAs.
Claim 18
Dependent Claim
16 words
A Pseudomorphic HEMT as recited in claim 13 , wherein 0.4≧y≧0.6 for said etch stop layer.
Claim 19
Dependent Claim
24 words
A Pseudomorphic HEMT as recited in claim 1 further comprising a spacer layer disposed between said semiconductor layer and said layer of silicon atoms.
Claim 20
Dependent Claim
15 words
A Pseudomorphic HEMT as recited in claim 16 wherein said spacer layer is n-doped AlGaAs.
Claim 21
Dependent Claim
24 words
A Pseudomorphic HEMT as recited in claim 7 further comprising a layer of silicon atoms disposed between said spacer layer and said Schottky layer.
Claim 22
Dependent Claim
15 words
A Pseudomorphic HEMT as recited in claim 18 wherein said spacer layer is n-doped AlGaAs.
Claim 23
Dependent Claim
14 words
A pseudormorphic HEMT as recited in claim 12 wherein said spacer layer is AlGaAs.
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