EP0226383A2
Expired / Lapsed
EP
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Resonant-tunneling transistor
Assignee: Fujitsu Ltd
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Filing: 1986-12-02
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Granted: —
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Expires: 2006-12-02
Abstract
Abstract A resonant-tunneling heterojunction bipolar transistor (RHBT) device, having a superlattice structure and a PN junction, includes an emitter layer (17), a base layer (14), a collector layer (13) operatively facing the base layer to form a PN junction at the face between the base layer and the collector layer, and a superlattice structure (16) including at least one quantum well defining a sub-band of energy at which carriers resonant-tunnel therethrough, formed at least in the emitter layer and operatively facing the base layer. The RHBT has differential negative resistance characteristics for realizing a variety of logic circuits and includes an electron resonance and a positive hole resonance, for which the generation condition is changeable in response to a mole fraction of material of the emitter layer. Such an RHBT, unlike a prior RHET, can be made to operate satisfactorily at normal ambient temperatures with adequate current gain.
Inventors
- 👤 Naoki Yokohama
- 👤 Kenichi Imamura
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 13:45
CPC Classifications
H; H10; H10D; H10D62/00; H10D62/10; H10D62/13; H10D62/165; B; B82; B82Y; B82Y10/00; B82Y30/00; H10D10/00; H10D10/80; H10D10/821; H10D10/881
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
70 words
A resonant-tunneling heterojunction bipolar transistor device comprising: an emitter layer; a base layer; a collector layer operatively facing said base layer to form a PN junction at the face between said base layer and said collector layer; and a superlattice structure including at least one quantum well defining a sub-band of energy at which carriers resonant-tunnel therethrough, formed at least in said emitter layer and operatively facing said base layer.
Claim 2
Dependent Claim
70 words
A resonant-tunneling heterojunction bipolar transistor device comprising: an emitter layer; a base layer; a collector layer operatively facing said base layer to form a PN junction at the face between said base layer and said collector layer; and a superlattice structure including at least one quantum well defining a sub-band of energy at which carriers resonant-tunnel therethrough, formed at least in said emitter layer and operatively facing said base layer.
Claim 3
Dependent Claim
50 words
A resonant-tunneling heterojunction bipolar transistor device according to claim 1, wherein said resonance includes a resonance of electrons and a resonance of positive holes, a generation condition of said electron resonance and said positive hole resonance being changed in response to a mole fraction of material in said emitter layer.
Claim 4
Dependent Claim
15 words
A resonant-tunneling heterojunction bipolar transistor device according to claim 2, wherein said material comprises aluminium.
Claim 5
Dependent Claim
27 words
A resonant-tunneling heterojunction bipolar transistor device according to claim 1, 2, or 3, wherein said superlattice structure is formed between said emitter layer and said base layer.
Claim 6
Dependent Claim
37 words
A resonant-tunneling heterojunction bipolar transistor device according to any preceding claim, wherein said emitter layer comprises an n-type semiconductor material, said base layer comprises a p-type semiconductor material, and said collector layer comprises an n-type semiconductor material.
Claim 7
Dependent Claim
41 words
A resonant-tunneling heterojunction bipolar transistor device according to any one of claims 1 to 5, wherein said emitter layer comprises a p-type semiconductor material, said base layer comprises an n-type semiconductor material, and said collector layer comprises a p-type semiconductor material.
Claim 8
Dependent Claim
70 words
A'resonant-tunneling heterojunction bipolar transistor device according to any preceding claim, said transistor device having a differential negative-resistance characteristic with at least one resonant point in a relationship between a current flowing in and said base layer and a voltage between said base and emitter layers, and having at least two stable base current values at both sides of said resonant point on said characteristic, defined by said changeable base-emitter voltage.
Claim 9
Dependent Claim
75 words
A resonant-tunneling heterojunction bipolar transistor device according to any one of claims 1 to 6, said transistor device having a differential negative-resistance characteristic with at least one resonant point in a relationship between a current flowing in and said collector layer and a voltage between said base and emitter layers, and having at least two stable collector current values at both sides of said resonant point on said characteristic, defined by said changeable base-emitter voltage.
Claim 10
Dependent Claim
93 words
Logic circuitry comprising: a resonant-tunneling heterojunction bipolar transistor device as claimed in claim 7; current source means ohmic-connected to said base layer of said transistor device and supplying a constant current to said base layer; load means ohmic-connected to said collector layer of said transistor device: and output means operatively connected to a commonly connected point of said load means and said collector layer, for outputting a voltage defined by a change of a current flowing through said collector layer, which voltage is varied in response to said two stable base current values.
Claim 11
Dependent Claim
41 words
Logic circuitry comprising: a resonant-tunneling heterojunction bipolar transistor device as claimed in claim 8; at least two input resistors operatively connected to said base of said transistor device; and an output resistor operatively connected to said collector of said transistor device.
References Cited (Backward Citations)
No citation records indexed.
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