US4912451A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heterojunction magnetic field sensor
Assignee: DIRECTOR-GENERAL OF AGENCY OF INDUSTRIAL SCIENCE AND TECHNOLOGY A CORP OF JAPAN
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Filing: 1988-12-29
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Granted: 1990-03-27
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Expires: 2008-12-29
Abstract
Abstract The heterojunction magnetic field sensor is basically a heterojunction structure forming a two-dimensional electron gas layer having a high carrier mobility at the junction portion of at least two different kinds of semiconductor layers having a different band gap, respectively, and further, at least one semiconductor layer having a quantum well structure is provided adjacent to and in contact with the two dimensional electron gas layer, the energy level of the ground state subband thereof being higher than that of the two-dimensional electron gas layer. This heterojunction magnetic field sensor has a high sensitivity which is not saturated even under a high electric field and provides an enhanced output even under the high electric field.
Inventors
- 👤 Yoshinobu Sugiyama
- 👤 Munecazu Tacano
- 👤 Hajime Soga
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:50
CPC Classifications
H; H10; H10N; H10N52/00; H10N52/101
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
151 words
A heterojunction magnetic field sensor comprising, a semi-insulating semiconductor substrate, a first semiconductor layer formed on said substrate as a buffer layer, a second semiconductor layer formed on said first semiconductor layer and including a spacer layer and a carrier supply layer therein, and at least one heterojunction structure formed between at least two of said layers arranged adjacent to each other, the band gap of each layer being different, at least a two-dimensional electron gas layer formed at the interface of the heterojunction of one of two seminconductor layers consisting of said heterojunction structure, having a band gap being smaller than that of another layer, said heterojunction magnetic field sensor being further characterized in that, at least a quantum well structure, a ground state subband thereof being higher than that of said two-dimensional electron gas layer is provided in said spacer layer arranged adjacent to the two-dimensional electron gas layer.
Claim 2
Dependent Claim
151 words
A heterojunction magnetic field sensor comprising, a semi-insulating semiconductor substrate, a first semiconductor layer formed on said substrate as a buffer layer, a second semiconductor layer formed on said first semiconductor layer and including a spacer layer and a carrier supply layer therein, and at least one heterojunction structure formed between at least two of said layers arranged adjacent to each other, the band gap of each layer being different, at least a two-dimensional electron gas layer formed at the interface of the heterojunction of one of two seminconductor layers consisting of said heterojunction structure, having a band gap being smaller than that of another layer, said heterojunction magnetic field sensor being further characterized in that, at least a quantum well structure, a ground state subband thereof being higher than that of said two-dimensional electron gas layer is provided in said spacer layer arranged adjacent to the two-dimensional electron gas layer.
Claim 3
Dependent Claim
15 words
A sensor according to claim 1, wherein said carrier supply layer has a superlattice structure.
Claim 4
Dependent Claim
28 words
A sensor according to claim 1, wherein said spacer layer having a quantum well structure is formed in said second layer and in contact with said buffer layer.
Claim 5
Dependent Claim
32 words
A sensor according to claim 3, wherein a two-dimensional electron gas layer is formed at the interface of the heterojunction between said buffer layer and said layer having the quantum well structure.
Claim 6
Dependent Claim
45 words
A sensor according to claim 1, wherein a two-dimensional electron gas layer is formed at the interface of the heterojunction between said spacer with quantum well structure and a semiconductor layer adjacently contacted with said spacer layer, both of them being in the second layer.
Claim 7
Dependent Claim
16 words
A sensor according to claim1, wherein said semi-insulating semiconductor substrate consists of a non-doped GaAs layer.
Claim 8
Dependent Claim
16 words
A sensor according to claim 1, wherein said buffer layer consists of a non-doped GaAs layer.
Claim 9
Dependent Claim
38 words
A sensor according to claim 1, wherein said layer having the quantum well structure consists of a combination of a plurality of different kinds of semiconductor layers selected from the following combinations, AlAs/GaAs/AlAs, AlAs/GaAs/AlGaAs, AlGaAs/GaAs/AlGaAs, AlGaAs/GaAs/AlGaAs/GaAs/AlGaAs, and AlAs/GaAs/AlAs/GaAs/AlAs.
Claim 10
Dependent Claim
17 words
A sensor according to claim 1, wherein said carrier supply layer consists of an Si-doped AlGaAs layer.
Claim 11
Dependent Claim
24 words
A sensor according to claim 2, wherein said carrier supply layer having said superlattice structure consists of a combination of semiconductor layers of GaAs/n-GaAs/GaAs/AlAs.
Claim 12
Dependent Claim
147 words
A sensor which comprises, a substrate formed of a GaAs layer, a first layer as a buffer layer formed as a GaAs layer on said substrate, a second layer composed of a spacer layer and a carrier supply layer epitaxially-grown on said first layer, said spacer layer consisting of at least three different layers of AlAs/GaAs/AlGaAs or AlAs/GaAs/AlAs, accumulated in that order on a top surface of said first layer to form a quantum well structure and said carrier supply layer is formed as an Si-doped AlGaAs layer mounted on a top surface of said AlGaAs layer of the quantum well structure, a two-dimensional electron gas layer being formed between said GaAs layer in said first layer and said AlAs layer as the most bottom layer in the quantum well structure in said spacer layer and, a surface layer made of a doped or non-doped GaAs layer.
Claim 13
Dependent Claim
147 words
A sensor which comprises, a substrate formed of a GaAs layer, a first layer as a buffer layer formed as a GaAs layer on said substrate, a second layer composed of a spacer layer and a carrier supply layer epitaxially-grown on said first layer, said spacer layer consisting of at least three different layers of AlAs/GaAs/AlGaAs or AlAs/GaAs/AlAs, accumulated in that order on a top surface of said first layer to form a quantum well structure and said carrier supply layer is formed as an Si-doped AlGaAs layer mounted on a top surface of said AlGaAs layer of the quantum well structure, a two-dimensional electron gas layer being formed between said GaAs layer in said first layer and said AlAs layer as the most bottom layer in the quantum well structure in said spacer layer and, a surface layer made of a doped or non-doped GaAs layer.
Claim 14
Dependent Claim
46 words
A sensor according to claim 11, wherein said carrier supply layer consists of another combination of different four layers of GaAs/n-GaAs/GaAs/AlAs, accumulated in this order on a top surface of said AlGaAs layer or AlAs layer of said quantum well structure to form a superlattice structure.
Claim 15
Dependent Claim
28 words
A sensor according to claim 11, wherein said quantum well structure consists of another combination of different layers of AlGaAs/GaAs/AlGaAs/GaAs/AlGaAs or AlAs/GaAs/AlAs/GaAs/AlAs, to form two quantum well structures.
Claim 16
Dependent Claim
28 words
A sensor according to claim 10 or 12, wherein said carrier supply layer is formed of by stacking a plurality of the unit combination of layers of GaAs/n-GaAs/GaAs/AlAs.
References Cited (Backward Citations)
US4827218A
Cited
JPS6354785A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-03-26 | 1993-09-25 | 1994-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-03-26 | 1997-09-25 | 1998-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-03-26 | 2001-09-25 | 2002-03-27 | $7700.00 | Window Closed / Lapsed |