EP0283276A2
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EP
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Semiconductor device having heterojunction and method for producing same
Assignee: Fujitsu Ltd
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Filing: 1988-03-17
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Granted: —
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Expires: 2008-03-17
Abstract
Abstract A semiconductor device comprising a semiconductor heterostructure (42, 48) formed on a substrate (41); source (43) and drain (44) electrodes formed on the semiconductor heterostructure; and a plurality of control electrodes (45, 49) arranged at predetermined positions between the source (43) and drain (44) electrodes at a predetermined spacing. A portion of each of the control electrodes (45, 49) is embedded so that it is in direct contact with a section of the semiconductor heterostructure (42, 48). The charge carriers, which can only freely move in the plane of a thin semiconductor well layer (42C, 48B) of the semiconductor heterostructure (42, 48) are further confined by the closely spaced control electrodes (45, 49) in a direction perpendicular to the source /drain direction so that one dimensional carrier paths are formed between the control electrodes (45, 49) in the source/drain direction.
Inventors
- 👤 Yuji Awano
- 👤 Satoru Asai
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 05:06
CPC Classifications
B; B82; B82Y; B82Y10/00; H; H10; H10D; H10D30/00; H10D30/40; H10D30/43; H10D64/00; H10D64/20; H10D64/27; H10D64/311; H10D64/411
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
118 words
A semiconductor device comprising: a heterojunction semiconductor layer (42, 48) formed on a substrate (41), having a structure including an undoped semiconductor layer (42C, 48B) sandwiched between doped semiconductor layers (42A, 42B; 48A); two electrodes (43, 44) formed opposite to each other on said heterojunction semiconductor layer ; and a plurality of control electrodes (45, 49) arranged at predetermined positions between said two electrodes at a predetermined spacing, a portion of each control electrode being embedded in such a manner that said portion is in direct contact with a section of said heterojunction semiconductor layer, whereby the direction of the movement of carriers within said undoped semiconductor layer is made one-dimensional in the vicinity of said control electrodes.
Claim 2
Dependent Claim
118 words
A semiconductor device comprising: a heterojunction semiconductor layer (42, 48) formed on a substrate (41), having a structure including an undoped semiconductor layer (42C, 48B) sandwiched between doped semiconductor layers (42A, 42B; 48A); two electrodes (43, 44) formed opposite to each other on said heterojunction semiconductor layer ; and a plurality of control electrodes (45, 49) arranged at predetermined positions between said two electrodes at a predetermined spacing, a portion of each control electrode being embedded in such a manner that said portion is in direct contact with a section of said heterojunction semiconductor layer, whereby the direction of the movement of carriers within said undoped semiconductor layer is made one-dimensional in the vicinity of said control electrodes.
Claim 3
Dependent Claim
33 words
A device as set forth in claim 1, further comprising a common electrode (47) for interconnecting other portions, which are not embedded in said heterojunction semiconductor layer, of said plurality of control electrodes.
Claim 4
Dependent Claim
38 words
A device as set forth in claim 1 or 2, wherein said heterojunction semiconductor layer (42) is constituted by a single undoped semiconductor layer (42C) and two doped semiconductor layers (42A, 42B) sandwiching said undoped semiconductor layer therebetween.
Claim 5
Dependent Claim
28 words
A device as set forth in claim 3, wherein an electron affinity is lower in said doped semiconductor layers (42A, 42B) than in said undoped semiconductor layer (42C).
Claim 6
Dependent Claim
35 words
A device as set forth in claim 3, wherein the sum of an electron affinity and an energy gap is greater in said doped semiconductor layers (42A, 42B) than in said undoped semiconductor layer (42C).
Claim 7
Dependent Claim
39 words
A device as set forth in claim 1 or 2, wherein said heterojunction semiconductor layer (48) has a multi-layer structure wherein a plurality of doped semiconductor layers (48A) and a plurality of undoped semiconductor layers (48B) are deposited alternately.
Claim 8
Dependent Claim
27 words
A device as set forth in claim 6, wherein an electron affinity is lower in said doped semiconductor layers (48A) than in said undoped semiconductor layers (48B).
Claim 9
Dependent Claim
34 words
A device as set forth in claim 6, wherein the sum of an electron affinity and an energy gap is greater in said doped semiconductor layers (48A) than in said undoped semiconductor layers (48B).
Claim 10
Independent Claim
30 words
A device as set forth in any preceding claim, wherein said carriers within said undoped semiconductor layer travel through a gap defined by said predetermined spacing in a one-dimensional direction.
Claim 11
Dependent Claim
29 words
A device as set forth in claim 9, wherein said gap is 1000 Å or less, and the thickness of said undoped semiconductor layer is 100 Å or less.
Claim 12
Independent Claim
112 words
A method for producing a semiconductor device comprising the steps of: growing a heterojunction semiconductor layer on a substrate, said heterojunction semiconductor layer comprising a structure including an undoped semiconductor layer (42C, 48B) sandwiched between doped semiconductor layers (42A, 42B; 48A); forming two electrodes opposite to each other on said heterojunction semiconductor layer; and embedding a plurality of control electrodes at predetermined positions between said two electrodes at a predetermined spacing in such a manner that a portion of each control electrode is in direct contact with a section of said heterojunction semiconductor layer, whereby the direction of movement of the carriers is made one-dimensional in the vicinity of said control electrodes.
Claim 13
Independent Claim
112 words
A method for producing a semiconductor device comprising the steps of: growing a heterojunction semiconductor layer on a substrate, said heterojunction semiconductor layer comprising a structure including an undoped semiconductor layer (42C, 48B) sandwiched between doped semiconductor layers (42A, 42B; 48A); forming two electrodes opposite to each other on said heterojunction semiconductor layer; and embedding a plurality of control electrodes at predetermined positions between said two electrodes at a predetermined spacing in such a manner that a portion of each control electrode is in direct contact with a section of said heterojunction semiconductor layer, whereby the direction of movement of the carriers is made one-dimensional in the vicinity of said control electrodes.
Claim 14
Dependent Claim
27 words
A method as set forth in claim 11, further comprising a step of forming a common electrode so that said plurality of control electrodes are connected thereto.
Claim 15
Dependent Claim
43 words
A method as set forth in claim 11 or 12, wherein the step of growing said heterojunction semiconductor layer comprises a step of growing a first doped semiconductor layer, an undoped semiconductor layer and a second doped semiconductor layer by molecular beam epitaxy.
Claim 16
Dependent Claim
38 words
A method as set forth in claim 11 or 12, wherein the step of growing said heterojunction semiconductor layer comprises a step of growing a plurality of doped semiconductor layers and a plurality of undoped semiconductor layers alternately.
Claim 17
Independent Claim
117 words
A method for producing a semiconductor device comprising the steps of: growing a heterojunction semiconductor layer on a substrate, said heterojunction semiconductor layer comprising a structure including an undoped semiconductor layer (42C, 48B) sandwiched between doped semiconductor layers (42A, 42B; 48A); embedding a plurality of control electrodes at predetermined positions at a predetermined spacing in such a manner that a portion of each control electrode is in direct contact with a section of said heterojunction semiconductor layer, whereby the direction of movement of the carriers is made one-dimensional in the vicinity of said control electrodes; and forming two electrodes opposite to each other on either side of said plurality of control electrodes on said heterojunction semiconductor layer.
Claim 18
Independent Claim
117 words
A method for producing a semiconductor device comprising the steps of: growing a heterojunction semiconductor layer on a substrate, said heterojunction semiconductor layer comprising a structure including an undoped semiconductor layer (42C, 48B) sandwiched between doped semiconductor layers (42A, 42B; 48A); embedding a plurality of control electrodes at predetermined positions at a predetermined spacing in such a manner that a portion of each control electrode is in direct contact with a section of said heterojunction semiconductor layer, whereby the direction of movement of the carriers is made one-dimensional in the vicinity of said control electrodes; and forming two electrodes opposite to each other on either side of said plurality of control electrodes on said heterojunction semiconductor layer.
Claim 19
Dependent Claim
27 words
A method as set forth in claim 15, further comprising a step of forming a common electrode so that said plurality of control electrodes are connected thereto.
Claim 20
Dependent Claim
43 words
A method as set forth in claim 15 or 16, wherein the step of growing said heterojunction semiconductor layer comprises a step of growing a first doped semiconductor layer, an undoped semiconductor layer and a second doped semiconductor layer by molecular beam epitaxy.
Claim 21
Dependent Claim
38 words
A method as set forth in claim 15 or 16, wherein the step of growing said heterojunction semiconductor layer comprises a step of growing a plurality of doped semiconductor layers and a plurality of undoped semiconductor layers alternately.
References Cited (Backward Citations)
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