US4881118A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor device
Assignee: Mitsubishi Electric Corp
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Filing: 1989-04-28
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Granted: 1989-11-14
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Expires: 2009-04-28
Abstract
Abstract One surface of a cathode sliding compensator is finished as an irregular surface while another surface thereof is finished as a sliding surface. The irregular surface is arranged to contact with a cathode electrode layer of a semiconductor element while the sliding surface is arranged to contact with a cathode conductor, and junction surfaces therebetween are electrically and mechanically connected by pressurization. Thus, the irregular surface bites into the cathode electrode layer to attain excellent electrical and mechanical connection between the cathode electrode layer and the cathode sliding compensator, while slidingness can be effectively retained between the cathode conductor and the cathode sliding compensator by the function of the sliding surface.
Inventors
- 👤 Kazuhiko Niwayama
- 👤 Tsutomu Nakagawa
- 👤 Futoshi Tokunoh
- 👤 Shigekazu Yoshida
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 03:08
CPC Classifications
H; H10; H10W; H10W76/00; H10W76/10; H10W76/12; H10W76/13; H10W76/138; H10W70/00; H10W70/20
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
176 words
A semiconductor device comprising: a semiconductor having a cathode electrode layer formed of aluminum on one surface thereof and an anode electrode layer formed on another surface thereof; an anode conductor arranged to contact with the surface of said anode electrode layer; a cathode sliding compensator made of a material having a thermal coefficient substantially similar to that of a semiconductor and having one surface being finished as an irregular surface and another surface being finished as a sliding surface, said irregular surface being arranged to contact with the surface of said cathode electrode layer; a cathode conductor made from a material having a thermal coefficient different than that of a semiconductor and arranged to contact with said sliding surface of said cathode sliding compensator; and means for holding said cathode conductor and said anode conductor so as to pressurize respective junction surfaces between said cathode conductor, said cathode sliding compensator, said semiconductor element and said anode conductor such that the irregular surface of said compensator penetrates any oxide formed on said aluminum cathode electrode layer.
Claim 2
Dependent Claim
176 words
A semiconductor device comprising: a semiconductor having a cathode electrode layer formed of aluminum on one surface thereof and an anode electrode layer formed on another surface thereof; an anode conductor arranged to contact with the surface of said anode electrode layer; a cathode sliding compensator made of a material having a thermal coefficient substantially similar to that of a semiconductor and having one surface being finished as an irregular surface and another surface being finished as a sliding surface, said irregular surface being arranged to contact with the surface of said cathode electrode layer; a cathode conductor made from a material having a thermal coefficient different than that of a semiconductor and arranged to contact with said sliding surface of said cathode sliding compensator; and means for holding said cathode conductor and said anode conductor so as to pressurize respective junction surfaces between said cathode conductor, said cathode sliding compensator, said semiconductor element and said anode conductor such that the irregular surface of said compensator penetrates any oxide formed on said aluminum cathode electrode layer.
Claim 3
Dependent Claim
25 words
A semiconductor device in accordance with claim 1, wherein surface roughness of said irregular surface of said cathode sliding compensator is 1 to 5 μm.
Claim 4
Dependent Claim
26 words
A semiconductor device in accordacne with claim 1, wherein surface roughness of said sliding surface of said cathode sliding compensator is not more than 0.5 μm.
Claim 5
Dependent Claim
25 words
A semiconductor device in accordance with claim 1, wherein said cathode sliding compensator is prepared by a material selected from molybdenum, tungsten, kovar and tantalum.
Claim 6
Dependent Claim
20 words
A semiconductor device in accordance with claim 1, wherein a plurality of said cathode sliding compensators are employed in lamination.
Claim 7
Dependent Claim
28 words
A semiconductor device in accordance with claim 5, wherein said plurality of cathode sliding compensators are formed by metal materials which are different in type from each other.
Claim 8
Dependent Claim
15 words
A semiconductor device in accordance with claim 1, wherein said semiconductor element is a thyristor.
Claim 9
Dependent Claim
15 words
A semiconductor device in accordance with claim 1, wherein said semiconductor element is a diode.
Claim 10
Dependent Claim
23 words
A semiconductor device in accordance with claim 1, wherein an insertion plate is provided between said cathode sliding compensator and said cathode conductor.
Claim 11
Dependent Claim
16 words
A semiconductor device in accordance with claim 9, wherein said insertion plate is made of silver.
Claim 12
Dependent Claim
22 words
A semiconductor device in accordance with claim 1, wherein an insertion plate is provided between said semiconductor element and said anode conductor.
Claim 13
Dependent Claim
16 words
A semiconductor device in accordance with claim 11, wherein said inseriton plate is made of silver.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-11-13 | 1993-05-15 | 1993-11-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-11-13 | 1997-05-15 | 1997-11-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-11-13 | 2001-05-15 | 2001-11-14 | $7700.00 | Window Closed / Lapsed |