US4825264A
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Resonant tunneling semiconductor device
Assignee: Fujitsu Ltd
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Filing: 1987-08-04
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Granted: 1989-04-25
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Expires: 2007-08-04
Abstract
Abstract A resonant tunneling semiconductor device having a large peak-to-valley current density J p /J v ratio comprises an InP substrate, a first contact compound semiconductor lattice-matched to Inp, a first barrier layer of (In 0 .52 Al 0 .48 As) z (In 0 .53 Ga 0 .47 As) 1-z , (0<z≦1), a well layer of In 1-y Ga y As, (0.48≧y≧0.46), a second barrier layer of (In 0 .52 Al 0 .48 As) z -(In 0 .53 Ga 0 .47 As) 1-z , (0<z≦1), and a second contact layer compound semiconductor lattice-matched to InP:The first and second barrier layers and the well layer forming a quantum-well structure. Instead of the quantum-well structure above, it is possible to adopt the quantum-well structure of strained-layers comprising first and second barrier layers which are of In 1-x Al x As (0.48<x≦1) and have a thickness of 0.5 to 10.0 nm.
Inventors
- 👤 Tsuguo Inata
- 👤 Shunichi Muto
- 👤 Toshio Fujii
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 11:24
CPC Classifications
H; H10; H10D; H10D10/00; H10D10/80; H10D10/821; H10D10/881; B; B82; B82Y; B82Y10/00; H10D48/00; H10D48/30; H10D48/32; H10D48/36; H10D48/362; H10D62/00; H10D62/80; H10D62/82; H10D62/824; H10D8/00; H10D8/01; H10D8/053; H10D8/70; H10D8/755
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
221 words
(Once Amended) A resonant tunneling semiconductor device comprising: an InP substrate; a first contact compound semiconductor layer formed on said InP substrate and lattice-matched to InP; a first barrier layer of (In 0 .52 Al 0 .48 As) z (In 0 .53 Ga 0 .47 As) 1-z (0<z≦1), formed on said first contact compound semiconductor layer and lattice-matched to InP; a well layer of In 1-y Ga y As formed on said first barrier layer and substantially latticed-matched to InP; a second barrier layer of (In 0 .52 Al 0 .48 As) z (In 0 .53 Ga 0 .47 As) 1-z (0<z≦1) formed on said well layer and lattice-matched in InP; and a second contact compound semiconductor layer formed on said second barrier layer and lattice-matched to InP, said first barrier layer, said second barrier layer and said well-layer forming a quantum-well structure, and a bottom of a conduction band E c of said first and second contact compound semiconductor layers is lower than a first resonant level E o of the quantum-well structure under a nonbiased condition, said InP substrate, said first contact compound semiconductor layer, said first barrier layer, said well layer, said second barrier layer and said second contact compound semiconductor layer providing a negative differential resistance characteristic at resonance having a maximum/minimum current ratio greater than 5.5.
Claim 2
Dependent Claim
221 words
(Once Amended) A resonant tunneling semiconductor device comprising: an InP substrate; a first contact compound semiconductor layer formed on said InP substrate and lattice-matched to InP; a first barrier layer of (In 0 .52 Al 0 .48 As) z (In 0 .53 Ga 0 .47 As) 1-z (0<z≦1), formed on said first contact compound semiconductor layer and lattice-matched to InP; a well layer of In 1-y Ga y As formed on said first barrier layer and substantially latticed-matched to InP; a second barrier layer of (In 0 .52 Al 0 .48 As) z (In 0 .53 Ga 0 .47 As) 1-z (0<z≦1) formed on said well layer and lattice-matched in InP; and a second contact compound semiconductor layer formed on said second barrier layer and lattice-matched to InP, said first barrier layer, said second barrier layer and said well-layer forming a quantum-well structure, and a bottom of a conduction band E c of said first and second contact compound semiconductor layers is lower than a first resonant level E o of the quantum-well structure under a nonbiased condition, said InP substrate, said first contact compound semiconductor layer, said first barrier layer, said well layer, said second barrier layer and said second contact compound semiconductor layer providing a negative differential resistance characteristic at resonance having a maximum/minimum current ratio greater than 5.5.
Claim 3
Dependent Claim
32 words
A resonant tunneling semiconductor device according to claim 1, wherein said first contact compound semiconductor layer comprises a material selected from a group consisting of ternary compound semiconductor and quaternary compound semiconductor.
Claim 4
Dependent Claim
21 words
A resonant tunneling semiconductor device according to claim 2, wherein said ternary semiconductor comprises In 0 .53 Ga 0 .47 As.
Claim 5
Dependent Claim
36 words
A resonant tunneling semiconductor device according to claim 1, wherein the mole fraction "z" of said first barrier layer is equal to one and said first barrier layer comprises In 0 .52 Al 0 .48 As.
Claim 6
Dependent Claim
28 words
A resonant tunneling semiconductor device according to claim 1, wherein the mole fraction "y" of said well layer is selected from within a range of 0.48 to 0.46.
Claim 7
Dependent Claim
30 words
A resonant tunneling semiconductor device according to claim 5, wherein the mole fraction "y" is equal to 0.47 and said well layer comprises In 0 .53 Ga 0 .47 As.
Claim 8
Dependent Claim
37 words
A resonant tunneling semiconductor device according to claim 1, wherein (where) the mole fraction "z" of said second barrier layer is equal to one and said second barrier layer comprises In 0 .52 Al 0 .48 As.
Claim 9
Dependent Claim
34 words
A resonant tunneling semiconductor device according to claim 1, wherein said second contact compound semiconductor layer comprises a material selected from the group consisting of a ternary compound semiconductor and a quaternary compound semiconductor.
Claim 10
Dependent Claim
22 words
A resonant tunneling semiconductor device according to claim 8 wherein said ternary compound semiconductor comprises In 0 .53 Ga 0 .47 As.
Claim 11
Dependent Claim
30 words
A resonant tunneling semiconductor device according to claim 1, further comprising: a first electrode contacting said first contact compound layer; and a second electrode contacting said second contact compound layer.
Claim 12
Dependent Claim
94 words
A resonant tunneling semiconductor device according to claim 1, further comprising: a collector layer of a compound semiconductor formed on said InP substrate, and said collector layer having a first conductivity type; and a collector barrier layer of a compound semiconductor formed on said collector layer, and said collector barrier layer forming a barrier at a junction with said collector layer; said first contact compound semiconductor layer comprising a base layer and having the first conductivity type, and said second contact compound semiconductor layer comprising an emitter layer and having the first conductivity type.
Claim 13
Dependent Claim
71 words
A resonant tunneling semiconductor device according to claim 1, further comprising: a collector layer of a compound semiconductor formed on said InP substrate, and said collector layer having a first conductivity type; said first contact compound semiconductor layer comprising a base layer and having a second conductivity type which is opposite to the first conductivity type, said second contact compound semiconductor comprising an emitter layer and having the first conductivity type.
Claim 14
Dependent Claim
171 words
A resonant tunneling semiconductor device comprising: an InP substrate; a first contact compound semiconductor layer formed on said InP substrate and lattice-matched to InP; a first barrier layer of In 1-x Al x As (0.48<x≦1) having a thickness from 0.5 to 10 nm, formed on said first contact compound semiconductor layer and not lattice-matched to InP; a well layer of In 1-y Ga y As formed on said first barrier layer and substantially lattice-matched to Inp; a second barrier layer of In 1-x Al x As (0.48<x≦1) having a thickness from 0.5 to 10 nm, formed on said well layer and not lattice-matched to InP; and a second contact compound semiconductor layer formed on said second barrier layer and lattice-matched to InP; said first barrier layer, said second barrier layer and said well-layer forming a quantum-well structure of strained-layers whereby a bottom of a conduction band E c of said first and second contact layers is lower than a first resonant level E 0 of said quantum-well under a nonbiased condition.
Claim 15
Dependent Claim
171 words
A resonant tunneling semiconductor device comprising: an InP substrate; a first contact compound semiconductor layer formed on said InP substrate and lattice-matched to InP; a first barrier layer of In 1-x Al x As (0.48<x≦1) having a thickness from 0.5 to 10 nm, formed on said first contact compound semiconductor layer and not lattice-matched to InP; a well layer of In 1-y Ga y As formed on said first barrier layer and substantially lattice-matched to Inp; a second barrier layer of In 1-x Al x As (0.48<x≦1) having a thickness from 0.5 to 10 nm, formed on said well layer and not lattice-matched to InP; and a second contact compound semiconductor layer formed on said second barrier layer and lattice-matched to InP; said first barrier layer, said second barrier layer and said well-layer forming a quantum-well structure of strained-layers whereby a bottom of a conduction band E c of said first and second contact layers is lower than a first resonant level E 0 of said quantum-well under a nonbiased condition.
Claim 16
Dependent Claim
34 words
A resonant tunneling semiconductor device according to claim 13, wherein said first contact compound semiconductor layer comprises a material selected from the group consisting of a ternary compound semiconductor and a quaternary compound semiconductor.
Claim 17
Dependent Claim
21 words
A resonant tunneling semiconductor device according to claim 13, wherein said ternary semiconductor comprises In 0 .53 Ga 0 .47 As.
Claim 18
Dependent Claim
31 words
A resonant tunneling semiconductor device according to claim 13, wherein (where) the mole fraction "x" of said first barrier layer is equal to 1 and said first barrier layer comprises AlAs.
Claim 19
Dependent Claim
27 words
A resonant tunneling semiconductor device according to claim 13, wherein the mole fraction "y" of said well layer is selected from a range of 0.48 to 0.46.
Claim 20
Dependent Claim
30 words
A resonant tunneling semiconductor device according to claim 17, wherein the mole fraction "y" is equal to 0.47 and said well layer comprises In 0 .53 Ga 0 .47 As.
Claim 21
Dependent Claim
30 words
A resonant tunneling semiconductor device according to claim 13, wherein the mole fraction "x" of said second barrier layer is equal to 1 and said second barrier layer comprises AlAs.
Claim 22
Dependent Claim
25 words
A resonant tunneling semiconductor device according to claim 13, wherein the thickness of said first and second barrier layers is from 1.0 to 5.0 nm.
Claim 23
Dependent Claim
34 words
A resonant tunneling semiconductor device according to claim 13, wherein said second contact compound semiconductor layer comprises a material selected from the group consisting of a ternary compound semiconductor and a quaternary compound semiconductor.
Claim 24
Dependent Claim
21 words
A resonant tunneling semiconductor device according to claim 21 wherein said ternary semiconductor comprises In 0 .53 Ga 0 .47 As.
Claim 25
Dependent Claim
32 words
A resonant tunneling semiconductor device according to claim 13, further comprising: a first electrode contacting said first contact compound semiconductor layer; and a second electrode contacting said second contact compound semiconductor layer.
Claim 26
Dependent Claim
94 words
A resonant tunneling semiconductor device according to claim 13, further comprising: a collector layer of a compound semiconductor formed on said InP substrate, and said collector layer having a first conductivity type; and p1 a collector barrier layer of a compound semiconductor formed on said collector layer, and said collector barrier layer forming a barrier at a junction with said collector layer; said first contact compound semiconductor layer comprising a base layer and having the first conductivity type, said second contact compound semiconductor layer comprising an emitter layer and having the first conductivity type.
Claim 27
Dependent Claim
72 words
A resonant tunneling semiconductor device according to claim 13, further comprising: a collector layer of a compound semiconductor formed on said InP substrate, and said collector layer having a first conductivity type; said first contact compound semiconductor layer comprising a base layer and having a second conductivity type which is opposite to the first conductivity type, said second contact compound semiconductor layer comprising an emitter layer and having the first conductivity type.
Claim 28
Dependent Claim
28 words
A resonant tunneling semiconductor device according to claim 13, wherein said layers provide a negative differential resistance characteristic at resonance having a maximum/minumum current ratio greater than 5.5.
Claim 29
Dependent Claim
17 words
A resonant tunneling semiconductor device as recited in claim 27, wherein said ratio is greater that 10.
Claim 30
Dependent Claim
17 words
A resonant tunneling semiconductor device as recited in claim 1, wherein said ratio is greater that 10.
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