US4585706A
Expired / Lapsed
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Sintered aluminum nitride semi-conductor device
Assignee: Hitachi Ltd
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Filing: 1985-08-26
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Granted: 1986-04-29
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Expires: 2005-08-26
Abstract
Abstract A semi-conductor device comprising sintered aluminum nitride having a high thermal conductivity, which comprises at least 65% by weight of aluminum nitride, and at least one of beryllium, a beryllium compound, lithium and a lithium compound.
Inventors
- 👤 Yukio Takeda
- 👤 Satoru Ogihara
- 👤 Mitsuru Ura
- 👤 Kousuke Nakamura
- 👤 Tadamichi Asai
- 👤 Tokio Ohkoshi
- 👤 Yasuo Matsushita
- 👤 Kunihiro Maeda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 12:20
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/60; H10W70/67; H10W70/69; H10W70/692; C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/581; H10P; H10P14/00; H10P14/60; H10P14/69; H10P14/694; H10P14/6943; H10P14/69433; H10W72/00; H10W72/50; H10W72/531; H10W72/5363; H10W72/551; H10W72/552; H10W72/5524; H10W74/00; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12528; Y10T428/12535; Y10T428/12576; Y10T428/12583; Y10T428/12674
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
47 words
A semi-conductor device which comprises an insulating substrate of sintered aluminum nitride having a high thermal conductivity, which comprises at least 65% by weight of aluminum nitride and at least one of beryllium, beryllium compound, lithium and lithium compound, and a semi-conductor element disposed on the substrate.
Claim 2
Dependent Claim
47 words
A semi-conductor device which comprises an insulating substrate of sintered aluminum nitride having a high thermal conductivity, which comprises at least 65% by weight of aluminum nitride and at least one of beryllium, beryllium compound, lithium and lithium compound, and a semi-conductor element disposed on the substrate.
Claim 3
Dependent Claim
41 words
The semi-conductor device according to claim 1, 0.05 to 10% by weight of at least one of the beryllium and the beryllium compound in terms of beryllium atom is contained in the sintered aluminum nitride on the base of aluminum nitride.
Claim 4
Dependent Claim
40 words
The semi-conductor device according to claim 1, wherein 0.05-5% by weight of at least one of the lithium and the lithium compound in terms of lithium atom is contained in the sintered aluminum nitride on the basis of aluminum nitride.
Claim 5
Dependent Claim
181 words
The semi-conductor device according to claim 1, wherein 0.05 to 10% by weight of at least one of the beryllium and the beryllium compound in terms of beryllium atom and 0.05 to 5% by weight of at least one of the lithium and the lithium compound in terms of lithium atom are contained in the sintered aluminum nitride on the basis of aluminum nitride, and when at least one of the lithium and the lithium compound takes the major proportion, the sum total of at least one of the beryllium and the beryllium compound and at least one of the lithium and the lithium compound is not more than 5% by weight in terms of beryllium and lithium atoms, and when at least one of the beryllium and the beryllium compound takes the major portion, the sum total of at least one of the beryllium and the beryllium compound and at least one of the lithium and the lithium compound is not more than 10% by weight in the term of beryllium and lithium atoms on the basis of aluminum nitride.
Claim 6
Dependent Claim
44 words
The semi-conductor device according to claim 1, wherein not more than 5% by weight of at least one of Y 2 O 3 , MgO, Al 2 O 3 and SiO 2 in terms of atom is contained on the basis of aluminum nitride.
Claim 7
Dependent Claim
23 words
The semi-conductor device according to claim 1, wherein the sintered aluminum nitride has a density of 90% or more of its theoretical density.
Claim 8
Dependent Claim
24 words
The semi-conductor device according to claim 1, wherein the sintered aluminum nitride has a thermal conductivity of 0.2 cal/cm.sec.°C. or higher at room temperature.
Claim 9
Dependent Claim
25 words
The semi-conductor device according to claim 1, wherein the sintered aluminum nitride has an electrical resistivity of 10 12 Ω.cm or higher at room temperature.
Claim 10
Dependent Claim
31 words
The semi-conductor device according to claim 1, wherein the sintered aluminum nitride has an average coefficient of thermal expansion of 5×10 -6 /°C. or less between room temperature and 300° C.
Claim 11
Dependent Claim
32 words
The semi-conductor device according to claim 1, wherein the semi-conductor element is brazed to the surface of the insulating substrate through a metalized layer formed on the surface of the insulating substrate.
Claim 12
Dependent Claim
13 words
The semi-conductor device according to claim 1, wherein the semi-conductor element is silicon.
References Cited (Backward Citations)
US4364100A
Cited
JPS5832073A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-04-28 | 1989-10-28 | 1990-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-04-28 | 1993-10-28 | 1994-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-04-28 | 1997-10-28 | 1998-04-29 | $7700.00 | Window Closed / Lapsed |