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实习内容：
1、氮化铝粉末的生产工艺（国外专题数据库）
（1）、Rare earth-activated aluminum nitride powders and method of
making
Inventors
BING HAN
US
Applicants
OSRAM SYLVANIA INC
US
Priority
US 763689 P 31-Jan-2006
Classifications
International (2006.01): C04B 35/00
European: C04B 35/581; C01B 21/072; C09K 11/08J;
Abstract
Rare earth-activated aluminum nitride powders are made using a
solution-based approach to form a mixed hydroxide of aluminum and a rare
earth metal, the mixed hydroxide is then converted into an ammonium metal
fluoride, preferably a rare earth-substituted ammonium aluminum hexafluoride
((NH4)3Al1-xRExF6), and finally the rare earth-activated aluminum nitride is
formed by ammonolysis of the ammonium metal fluoride at a high temperature.
The use of a fluoride precursor in this process avoids sources of oxygen during
the final ammonolysis step which is a major source of defects in the powder
synthesis of nitrides. Also, because the aluminum nitride is formed from a
mixed hydroxide co-precipitate, the distribution of the dopants in the powder is
substantially homogeneous in each particle.
（2）、ALUMINUM NITRIDE SINTERED BODY AND METHOD OF
PRODUCING THE SAME 2 公开号 US5482905
申请号 US/08/178642
申请人 SUMITOMO ELECTRIC INDUSTRES LTDSUMITOMO ELECTRIC INDUSTRI发明人 NAKAAHATA SEIJI AMATSUURA TAKAHIRO SOGABE KOUICHI YAMAKIRA
HATA SEIJIMATSUURA TAKAHIROSOGABE KOUICHIYAMAKAWA AKIRA
申请日期 1994-01-05
授权日期 1996-01-09
国际分类 C04B35/58C04B35/58
美国专利分类 501/98.4501/98.4
代理人 Bierman; Jordan B.Bierman and Muserlianman; Jordan B.Bierman and Muser摘要An aluminum nitride sintered body comprising aluminum nitride
crystals belonging to a Wurtzite hexagonal crystal system wherein the 3 axes a,
b and c of the unit lattice of the crystal are defined such that the ratio b/a of the
lengths of the axes b and a is 1.000 near the center of the crystal grain and lies
within the range 0.997-1.003 in the vicinity of the grain boundary phase.
Aluminum nitride sintered body is produced by sintering a molded body of a
raw material powder having aluminum and nitrogen as its principal
components at a temperature of 1700.degree.-1900.degree. C. in a
non-oxidizing atmosphere having a partial pressure of carbon monoxide or
carbon of not more than 200 ppm and then cooling the sintered body to
1500.degree. C. or a lower temperature at a rate of 5.degree. C./min or less.
The aluminum nitride sintered body has a greatly improved thermal
conductivity and, therefore, is suitable for heat slingers, substrates or the like
for semiconductor devices.
权利要求1. An aluminum nitride sintered body comprising aluminum
nitride crystals belonging to a Wurtzite hexagonal crystal system wherein
three axes a, b, and c of a unit lattice of the crystal are defined whereby
a ratio b/a of the lengths of axes b and a is 1.000 near a center of the
crystal grain, and lies within a range of 0.997 to 1.003 in a vicinity
of a grain boundary phase, said sintered body containing at least one
compound selected from the group consisting of Ti, V, and Co. 3 2. An aluminum nitride sintered body as defined in claim 1 wherein the sintered
body has a thermal conductivity of 150 W/m.K or higher.
3. An aluminum nitride sintered body as defined in claim 1 wherein the sintered
body has a 3-point flexural strength of 35 kg/mm.sup.2 or higher.
4. A method of manufacturing an aluminum nitride sintered body comprising
adding, to a raw material powder comprising aluminum and nitrogen as its
principal components, 0.13 to 0.5% by weight of at least one compound
selected from the group consisting of Ti, V, and Co,
molding the raw material powder to form a molded body,
sintering said molded body at a temperature of 1700.degree. to 1900.degree.
C. in a non-oxidizing atmosphere having a partial pressure of carbon monoxide
or carbon of not more than 200 ppm to form a sintered body, and
cooling said sintered body to 1500.degree. C. or less, at a rate of 5.degree. C.
per minute, or less.
描述BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an aluminum nitride (AlN) sintered body having an
excellent thermal conductivity, and a method of manufacturing such a body.
2. Description of the Prior Art
Aluminum nitride has very good electrical insulation properties and a very high
thermal conductivity. For this reason, aluminum nitride sintered bodies are
used as a replacement for beryllia (BeO) in power transistor heat slingers or
the like, as a replacement for alumina (Al.sub.2 O.sub.3) in substrates or
packaging materials for semiconductor devices, and in laser tubes, etc.
Although the thermal conductivity of aluminum nitride sintered bodies is far
higher than that of other ceramic materials, the thermal conductivity of actual
aluminum nitride sintered bodies industrially produced does not exceed about
half the theoretical value of 320 W/mK. It is known that the thermal conductivity
of aluminum nitride sintered bodies largely reduce when it contains impurities,
such as silicon or oxygen, in solid solution. Recently, due to higher purity of the
