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US5250478A
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Aluminum nitride sintered body and process for preparation thereof
Assignee: Kyocera Corp
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Filing: 1992-01-17
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Granted: 1993-10-05
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Expires: 2012-01-17
Abstract
Abstract Disclosed is an aluminum nitride sintered body comprising aluminum nitride and a sintering aid, wherein the sintering aid is composed mainly of at least one component selected, as the oxide, from the group consisting of Yb2O3 and Er2O3, and the sintered body contains up to 0.5% by weight of Yb and/or Er as the metal and has a density of 3.2 to 3.3 g/cm3 and a heat conductivity of at least 170 W/mxk. If a CaO component is incorporated as the second sintering aid in an amount of up to 0.1% by weight, the heat conductivity is further increased.
Inventors
- 👤 Masanobu Ishida
- 👤 Yoshihiro Okawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:18
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/581
Claims Analysis
Total Claims: 43
Claim 1
Independent Claim
77 words
An aluminum nitride sintered body consisting essentially of: aluminum nitride and a sintering aid, wherein the sintered aid is composed of at least one component selected from the group consisting of Yb 2 O 3 and Er 2 O 3 , and the sintered body contains up to 0.5% by weight of Yb and/or Er as the metal and has a density of 3.2 to 3.3 g/cm 3 and a heat conductivity of at least 170 W/m·K.
Claim 2
Dependent Claim
77 words
An aluminum nitride sintered body consisting essentially of: aluminum nitride and a sintering aid, wherein the sintered aid is composed of at least one component selected from the group consisting of Yb 2 O 3 and Er 2 O 3 , and the sintered body contains up to 0.5% by weight of Yb and/or Er as the metal and has a density of 3.2 to 3.3 g/cm 3 and a heat conductivity of at least 170 W/m·K.
Claim 3
Dependent Claim
28 words
An aluminum nitride sintered body as set forth in claim 1, wherein the content of Yb and/or Er as the metal is from 0.01% to 0.2% by weight.
Claim 4
Dependent Claim
91 words
An aluminum nitride sintered body consisting essentially of: aluminum nitride and a sintering aid, wherein the sintering aid is composed of at least one component selected from the group consisting of Yb 2 O 3 and Er 2 O 3 and a CaO component, and the sintered body contains up to 0.5% by weight of Yb and/or Er as the metal and up to 0.1% by weight of Ca as the metal and has a density of 3.2 to 3.3 g/cm 3 and a heat conductivity of at least 170 W/m·K.
Claim 5
Dependent Claim
91 words
An aluminum nitride sintered body consisting essentially of: aluminum nitride and a sintering aid, wherein the sintering aid is composed of at least one component selected from the group consisting of Yb 2 O 3 and Er 2 O 3 and a CaO component, and the sintered body contains up to 0.5% by weight of Yb and/or Er as the metal and up to 0.1% by weight of Ca as the metal and has a density of 3.2 to 3.3 g/cm 3 and a heat conductivity of at least 170 W/m·K.
Claim 6
Dependent Claim
50 words
An aluminum nitride sintered body as set forth in claim 3, wherein the content of Yb and/or Er as the metal is up to 0.1% by weight and the content of Ca as the metal is up to 0.05% by weight, and the heat conductivity is at least 200 W/m·K.
Claim 7
Dependent Claim
27 words
An aluminum nitride sintered body according to claim 1 wherein the sintered body contains from 0.02% to 0.5% by weight of Yb and/or Er as the metal.
Claim 8
Dependent Claim
27 words
An aluminum nitride sintered body according to claim 1 wherein the sintered body contains from 0.01% to 0.2% by weight of Yb and/or Er as the metal.
Claim 9
Dependent Claim
27 words
An aluminum nitride sintered body according to claim 1 wherein the sintered body contains from 0.02% to 0.2% by weight of Yb and/or Er as the metal.
Claim 10
Dependent Claim
27 words
An aluminum nitride sintered body according to claim 3 wherein the sintered body contains from 0.01 to 0.5% by weight of Yb and/or Er as the metal.
Claim 11
Dependent Claim
27 words
An aluminum nitride sintered body according to claim 3 wherein the sintered body contains from 0.01 to 0.2% by weight of Yb and/or Er as the metal.
Claim 12
Dependent Claim
27 words
An aluminum nitride sintered body according to claim 3 wherein the sintered body contains from 0.02 to 0.2% by weight of Yb and/or Er as the metal.
Claim 13
Dependent Claim
39 words
An aluminum nitride sintered body according to claim 3 wherein the sintered body contains from 0.01 to 0.5% by weight of Yb and/or Er as the metal and from 0.01 to 0.1% by weight of Ca as the metal.
Claim 14
Dependent Claim
39 words
An aluminum nitride sintered body according to claim 3 wherein the sintered body contains from 0.01 to 0.1% by weight of Yb and/or Er as the metal and from 0.0005 to 0.0003% by weight of Ca as the metal.
Claim 15
Dependent Claim
39 words
An aluminum nitride sintered body according to claim 3 wherein the sintered body contains from 0.01 to 0.04% by weight of Yb and/or Er as the metal, and from 0.001 to 0.003% by weight of Ca as the metal.
Claim 16
Dependent Claim
81 words
An aluminum nitride sintered body consisting essentially of: aluminum nitride and a sintering aid wherein the sintering aid is composed of a compound of Yb and/or Er capable of being converted to an oxide of Yb and/or Er at the firing temperature, and the sintered body contains from 0.01 to 0.5% by weight of Yb and/or Er as the metal and has a density of 3.2 to 3.3 grams per cubic centimeter and a heat conductivity of at least 170 W/m·K.
Claim 17
Dependent Claim
81 words
An aluminum nitride sintered body consisting essentially of: aluminum nitride and a sintering aid wherein the sintering aid is composed of a compound of Yb and/or Er capable of being converted to an oxide of Yb and/or Er at the firing temperature, and the sintered body contains from 0.01 to 0.5% by weight of Yb and/or Er as the metal and has a density of 3.2 to 3.3 grams per cubic centimeter and a heat conductivity of at least 170 W/m·K.
Claim 18
Dependent Claim
39 words
An aluminum nitride sintered body according to claim 14 wherein the Yb and/or Er compound is selected from the group consisting of ytterbium oxide, ytterbium carbonate, ytterbium nitrate, ytterbium hydroxide, erbium oxide, erbium carbonate, erbium nitrate and erbium hydroxide.
Claim 19
Dependent Claim
104 words
An aluminum nitride sintered body consisting essentially of: aluminum nitride and a sintering aid wherein the sintering aid is composed of at least one component selected from the group consisting of ytterbium oxide, ytterbium carbonate, ytterbium nitrite, ytterbium hydroxide, erbium oxide, erbium carbonate, erbium nitrate and erbium hydroxide, and a CaO component, and wherein the sintered body contains from 0.01 to 0.5% by weight of ytterbium and/or erbium as the metal, and from 0.0005 to 0.1% by weight of Ca as the metal, and has a density of 3.2 to 3.3 grams per cubic centimeter and a heat conductivity of at least 170 W/m·K.
Claim 20
Dependent Claim
104 words
An aluminum nitride sintered body consisting essentially of: aluminum nitride and a sintering aid wherein the sintering aid is composed of at least one component selected from the group consisting of ytterbium oxide, ytterbium carbonate, ytterbium nitrite, ytterbium hydroxide, erbium oxide, erbium carbonate, erbium nitrate and erbium hydroxide, and a CaO component, and wherein the sintered body contains from 0.01 to 0.5% by weight of ytterbium and/or erbium as the metal, and from 0.0005 to 0.1% by weight of Ca as the metal, and has a density of 3.2 to 3.3 grams per cubic centimeter and a heat conductivity of at least 170 W/m·K.
Claim 21
Dependent Claim
130 words
A process for the preparation of an aluminum nitride sintered body, which comprises molding a composition comprising 85 to 97% by weight of an aluminum nitride powder and 3 to 15% by weight of a sintering aid selected from the group consisting of Yb 2 O 3 and Er 2 O 3 and firing the obtained molded body at a temperature of 1600° to 2000° C. in an non-oxidizing atmosphere containing at least 1 Torr of nitrogen gas to thereby evaporate the sintering aid until the content of Yb and/or Er as the metal in the sintered body is up to 0.5% by weight, and wherein at the step of firing the molded body, the average temperature-elevating rate from 1200° C. to the sintering temperature is lower than 40° C./min.
Claim 22
Dependent Claim
130 words
A process for the preparation of an aluminum nitride sintered body, which comprises molding a composition comprising 85 to 97% by weight of an aluminum nitride powder and 3 to 15% by weight of a sintering aid selected from the group consisting of Yb 2 O 3 and Er 2 O 3 and firing the obtained molded body at a temperature of 1600° to 2000° C. in an non-oxidizing atmosphere containing at least 1 Torr of nitrogen gas to thereby evaporate the sintering aid until the content of Yb and/or Er as the metal in the sintered body is up to 0.5% by weight, and wherein at the step of firing the molded body, the average temperature-elevating rate from 1200° C. to the sintering temperature is lower than 40° C./min.
Claim 23
Dependent Claim
25 words
A process according to claim 17, wherein carbon is incorporated in the non-oxidizing atmosphere and sintering of the molded body is effected in said atmosphere.
Claim 24
Dependent Claim
33 words
A process according to claim 17, wherein the composition to be molded comprises 90 to 95% by weight of the aluminum nitride powder and 5 to 10% by weight of the sintering aid.
Claim 25
Dependent Claim
150 words
A process for the preparation of an aluminum nitride sintered body, which comprises molding a composition comprising 85 to 97% by weight of aluminum nitride powder, 3 to 15% by weight of a first sintering aid selected from the group consisting of Yb 2 O 3 and Er 2 O 3 and a second sintering aid comprising 0.01 to 0.2% by weight of a calcium compound capable of being converted to CaO under sintering conditions, firing the obtained molded body in a non-oxidizing atmosphere to thereby evaporate the sintering aids until the content of Yb and/or Er as the metal in the sintered body is up to 0.5% by weight and the content of Ca as the metal is up to 0.1% by weight, and wherein at the step of firing the molded body, the average temperature-elevating rate from 1200° C. to the sintering temperature is lower than 40° C./min.
Claim 26
Dependent Claim
150 words
A process for the preparation of an aluminum nitride sintered body, which comprises molding a composition comprising 85 to 97% by weight of aluminum nitride powder, 3 to 15% by weight of a first sintering aid selected from the group consisting of Yb 2 O 3 and Er 2 O 3 and a second sintering aid comprising 0.01 to 0.2% by weight of a calcium compound capable of being converted to CaO under sintering conditions, firing the obtained molded body in a non-oxidizing atmosphere to thereby evaporate the sintering aids until the content of Yb and/or Er as the metal in the sintered body is up to 0.5% by weight and the content of Ca as the metal is up to 0.1% by weight, and wherein at the step of firing the molded body, the average temperature-elevating rate from 1200° C. to the sintering temperature is lower than 40° C./min.
Claim 27
Dependent Claim
25 words
A process according to claim 20, wherein carbon is incorporated in the non-oxidizing atmosphere and sintering of the molded body is effected in said atmosphere.
Claim 28
Dependent Claim
31 words
A process according to claim 20, wherein at the step of firing the molded body, the average temperature-elevating rate from 1200° C. to the sintering temperature is lower than 40° C./min.
Claim 29
Dependent Claim
130 words
A process for producing an aluminum nitride sintered body, the process including the following steps: molding a composition consisting essentially of aluminum nitride powder, and a sintering aid selected from the group consisting of Yb compounds and Er compounds capable of being converted to oxides of such compounds under firing conditions; and firing the obtained molded body at a temperature of 1600°-2000° C. in a non-oxidizing atmosphere containing at least one Torr of nitrogen gas to thereby evaporate the sintering aid until the content of Yb and/or Er as the metal in the sintered body ranges from 0.01 to 0.05% by weight as the metal, wherein at the step of firing the molded body, the average temperature-elevating rate from 1200° C. to the sintering temperature is lower than 40° C./min.
Claim 30
Dependent Claim
130 words
A process for producing an aluminum nitride sintered body, the process including the following steps: molding a composition consisting essentially of aluminum nitride powder, and a sintering aid selected from the group consisting of Yb compounds and Er compounds capable of being converted to oxides of such compounds under firing conditions; and firing the obtained molded body at a temperature of 1600°-2000° C. in a non-oxidizing atmosphere containing at least one Torr of nitrogen gas to thereby evaporate the sintering aid until the content of Yb and/or Er as the metal in the sintered body ranges from 0.01 to 0.05% by weight as the metal, wherein at the step of firing the molded body, the average temperature-elevating rate from 1200° C. to the sintering temperature is lower than 40° C./min.
Claim 31
Dependent Claim
36 words
A process according to claim 23 wherein the Yb and Er compounds are selected from the group consisting of ytterbium oxide, ytterbium carbonate, ytterbium nitrate, ytterbium hydroxide, erbium oxide, erbium carbonate, erbium nitrate and erbium hydroxide.
Claim 32
Dependent Claim
29 words
A process according to claim 24 wherein there is present 85 to 97% by weight of aluminum nitride powder and 3 to 15% by weight of the sintering aid.
Claim 33
Dependent Claim
27 words
A process according to claim 25 further including from 0.01 to 0.2% by weight of a calcium compound capable of being converted to CaO under sintering conditions.
Claim 34
Dependent Claim
12 words
An aluminum nitride sintered body produced by the process of claim 17.
Claim 35
Dependent Claim
12 words
An aluminum nitride sintered body produced by the process of claim 18.
Claim 36
Dependent Claim
12 words
An aluminum nitride sintered body produced by the process of claim 19.
Claim 37
Dependent Claim
12 words
An aluminum nitride sintered body produced by the process of claim 20.
Claim 38
Dependent Claim
12 words
An aluminum nitride sintered body produced by the process of claim 21.
Claim 39
Dependent Claim
12 words
An aluminum nitride sintered body produced by the process of claim 22.
Claim 40
Dependent Claim
12 words
An aluminum nitride sintered body produced by the process of claim 23.
Claim 41
Dependent Claim
12 words
An aluminum nitride sintered body produced by the process of claim 24.
Claim 42
Dependent Claim
12 words
An aluminum nitride sintered body produced by the process of claim 25.
Claim 43
Dependent Claim
12 words
An aluminum nitride sintered body produced by the process of claim 26.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-10-04 | 1997-04-05 | 1997-10-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-10-04 | 2001-04-05 | 2001-10-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-10-04 | 2005-04-05 | 2005-10-05 | $7700.00 | Window Closed / Lapsed |