IP Library › Granted Patent US 12,365,823
Granted Patent B2
US 12,365,823 · App. 16/886,153 · Granted Jul 22, 2025

AlN crystal preparation method, AlN crystals, and organic compound including AlN crystals

Inventors: Toru Ujihara (Nagoya, JP); Yukihisa Takeuchi (Nagoya, JP); Mingyu Chen (Nagoya, JP); Masashi Nagaya (Nagoya, JP)
Assignee: NATIONAL UNIVERSITY CORPORATION NAGOYA UNIVERSITY
C09K5/14C01B21/072C01B21/0722C30B25/005C30B29/38C30B29/62C01P2002/72C01P2004/01C01P2004/03C01P2004/04C01P2004/16C01P2006/32
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Quick Facts
Patent No.
US 12,365,823
App. No.
16/886,153
Granted
Jul 22, 2025
Kind
B2
Abstract

A method for producing AlN crystals includes using at least one element, excluding Si, that satisfies a condition under which the element forms a compound with neither Al nor N or a condition under which the element forms a compound with any of Al and N provided that the standard free energy of formation of the compound is larger than that of AlN; melting a composition containing at least Al and the element; and reacting the Al vapor with nitrogen gas at a predetermined reaction temperature to produce AlN crystals.

Claims (40)

1. A method for producing AlN crystals, comprising:

using an alloy comprising Al and an element, excluding Si, that satisfies a condition under which the element forms a compound with neither Al nor N or a condition under which the element forms a compound with either of Al and N provided that the standard free energy of formation of the compound is larger than that of AlN;

melting the alloy;

introducing nitrogen gas to establish an atmosphere of nitrogen gas;

reacting the Al with the nitrogen gas at a predetermined temperature and at a predetermined pressure to produce AlN crystals, wherein the AlN crystals comprise AlN whiskers,

wherein a first interaction energy between Al and the element becomes negative, and an absolute value of the first interaction energy is larger than a second interaction energy between Al and Ge.

2. The method for producing AlN crystals according to claim 1 , wherein the element is any of Li, Cr, Fe, Co, Ni, Cu, and Sr.

3. The method for producing AlN crystals according to claim 1 , further comprising:

peeling the AlN whiskers from the alloy.

4. The method for producing AlN crystals according to claim 1 , wherein:

reacting the Al with the nitrogen gas comprises reacting Al vapor with the nitrogen gas.

5. The method for producing AlN crystals according to claim 1 , wherein:

the predetermined temperature is 1450-1800° C.

6. The method for producing AlN crystals according to claim 5 , wherein:

the predetermined pressure is from several mm Hg to atmospheric pressure.

7. The method for producing AlN crystals according to claim 5 , wherein:

the predetermined pressure is greater than atmospheric pressure.

8. A method for producing AlN crystals, comprising:

using an alloy consisting of Al and Fe, excluding Si;

melting the alloy;

introducing nitrogen gas to establish an atmosphere of nitrogen gas;

reacting the Al with nitrogen gas at a predetermined temperature and at a predetermined pressure to produce AlN crystals, wherein the AlN crystals comprise AlN whiskers,

wherein a first interaction energy between Al and Fe becomes negative, and

wherein an absolute value of the first interaction energy is larger than a second interaction energy between Al and Ge.

9. The method for producing AlN crystals according to claim 8 , further comprising:

peeling the AlN whiskers from the alloy.

10. The method for producing AlN crystals according to claim 8 , wherein:

the predetermined temperature is 1450-1800° C.

11. The method for producing AlN crystals according to claim 8 , wherein:

the predetermined pressure is several mm Hg to atmospheric pressure.

12. The method for producing AlN crystals according to claim 8 , wherein:

the predetermined pressure is greater than atmospheric pressure.

13. The method for producing AlN crystals according to claim 8 , wherein:

a ratio of Al to Fe is from 10:90 to 30:70.

14. The method for producing AlN crystals according to claim 8 , wherein:

the AlN whiskers have a diameter of about 0.1 to 1 μm and a length of about 10 to 50 μm.

15. The method for producing AlN crystals according to claim 8 , wherein:

the AlN whiskers have a diameter of about 0.5 to 1.5 μm and a length of about 50 μm to 1 mm.

16. The method for producing AlN crystals according to claim 8 , wherein:

the AlN whiskers have a diameter of about 1 to 2 μm and a length of greater than 1 mm.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 17, 2020
From: UJIHARA, TORU; TAKEUCHI, YUKIHISA; CHEN, MINGYU; NAGAYA, MASASHI
To: NATIONAL UNIVERSITY CORP. NAGOYA UNIVERSITY
Reel/Frame 052959/0563 →
Priority Claims (2)
JP 2014-112691 · May 30, 2014 · national
JP 2014-181289 · Sep 5, 2014 · national
Continuity (2)
Division 15314789
Related Publication 20210009885A1 · Jan 14, 2021
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