EP0080714A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Hetero-junction semiconductor device
Assignee: Hitachi Ltd
•
Filing: 1982-11-26
•
Granted: —
•
Expires: 2002-11-26
Abstract
Abstract A semiconductor device is disclosed which has at least a hetero-junction formed by a first semiconductor layer (22) and a second semiconductor layer (23) where the forbidden band gap of the said first semiconductor (22) is smaller than that of the said second semiconductor (23), at least one pair of electrodes (29, 30) connected electronically to the said first semiconductor (22) and a means (28) to control the carrier density in the said first semiconductor layer (22). Effectively no impurities are included in the region of the first semiconductor layer (22) under the means (28) to control the carriers, but impurities are included in the regions (24) adjacent to the said pair of electrodes (29, 30). The density of the impurities in these regions (24) is preferably larger than 10 16 cm- 3 .
Inventors
- 👤 Yasuhiro Shiraki
- 👤 Yoshimasa Murayama
- 👤 Yoshifumi Katayama
- 👤 Eiichi Maruyama
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 11:27
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/80; H10D30/40; H10D30/47; H10D30/471; H10D30/473; H10D30/4732; H10D30/475; H10D30/4755; H10D84/00; H10D84/01; H10D84/0123; H10D84/0126; H10D84/0158; H10D84/02; H10D84/05
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
144 words
A semiconductor device comprising: a semiconductor substrate (21), at least a first semiconductor layer (22) and second semiconductor layer (23) formed over said substrate (21), said first and second semiconductor layers (22, 23) forming a hetero-junction at the interface between them, said first semiconductor layer (22) having a relatively small forbidden band gap as compared with that of said second semiconductor layer (23), at least one pair of electrodes (29, 30) connected electronically to said first semiconductor layer (22), and a means (28) to control the carriers in said first semiconductor layer (22) wherein impurities are not included substantially in the said first and second semiconductor layers (22, 23) under said means (28) to control carriers and are included at least in either said first or second semiconductor layer (22, 23) in the regions (24) adjacent to said one pair of electrodes (29, 30).
Claim 2
Dependent Claim
144 words
A semiconductor device comprising: a semiconductor substrate (21), at least a first semiconductor layer (22) and second semiconductor layer (23) formed over said substrate (21), said first and second semiconductor layers (22, 23) forming a hetero-junction at the interface between them, said first semiconductor layer (22) having a relatively small forbidden band gap as compared with that of said second semiconductor layer (23), at least one pair of electrodes (29, 30) connected electronically to said first semiconductor layer (22), and a means (28) to control the carriers in said first semiconductor layer (22) wherein impurities are not included substantially in the said first and second semiconductor layers (22, 23) under said means (28) to control carriers and are included at least in either said first or second semiconductor layer (22, 23) in the regions (24) adjacent to said one pair of electrodes (29, 30).
Claim 3
Dependent Claim
23 words
The device of claim 1, wherein said first semiconductor layer (22) is of GaAs and said second semiconductor layer (23) is of AlGaAs.
Claim 4
Dependent Claim
48 words
The device of claim 1 or 2, wherein said first semiconductor layer (22) is of Al x Ga 1-X As and said second semiconductor layer (23) is of Al y Ga 1-Y As, where 0 < x < 0.5, 0 < y < 0.5 and x < y.
Claim 5
Dependent Claim
20 words
The device of claim 2 or 3, further comprising a GaAs layer (35) formed on said second semiconductor layer (22).
Claim 6
Independent Claim
33 words
The device of any of claims 1 to 4, wherein the substrate (21), the first semiconductor layer (22) and the second semiconductor layer (23) are either of III-V semiconductors or III-V semiconductor alloys.
Claim 7
Independent Claim
54 words
The device of any of claims 1 to 5, further comprising an impurity region which is formed in said second semiconductor layer (23) under said means (28) to control the carriers and is determined so as to be apart from said hetero-junction at the interface between said first and second semiconductor layers (22, 23).
Claim 8
Independent Claim
63 words
The device of any of claims 1 to 6, wherein the impurity density of said first semiconductor layer (22) under said means (28) to control the carriers is smaller than 10 17 cm-3 and the impurity density of said region (24) in said first semiconductor layer (22) adjacent to said pair of electrodes (29, 30) is larger than 10 16 cm -3 .
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.