JPS63291878A - Production of aluminum nitride sintered material - Google Patents

Production of aluminum nitride sintered material

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Publication number
JPS63291878A
JPS63291878A JP62127204A JP12720487A JPS63291878A JP S63291878 A JPS63291878 A JP S63291878A JP 62127204 A JP62127204 A JP 62127204A JP 12720487 A JP12720487 A JP 12720487A JP S63291878 A JPS63291878 A JP S63291878A
Authority
JP
Japan
Prior art keywords
earth metal
powder
solution
hydroxide
rare earth
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP62127204A
Other languages
Japanese (ja)
Other versions
JP2548192B2 (en
Inventor
Naoya Nunogaki
布垣 尚哉
Tetsuo Toyama
哲男 外山
Shinichi Shirasaki
信一 白崎
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
National Institute for Research in Inorganic Material
Denso Corp
Original Assignee
National Institute for Research in Inorganic Material
NipponDenso Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by National Institute for Research in Inorganic Material, NipponDenso Co Ltd filed Critical National Institute for Research in Inorganic Material
Priority to JP62127204A priority Critical patent/JP2548192B2/en
Publication of JPS63291878A publication Critical patent/JPS63291878A/en
Application granted granted Critical
Publication of JP2548192B2 publication Critical patent/JP2548192B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Abstract

PURPOSE:To obtain the titled dense sintered material having high thermal conductivity, providing a circuit substrate having excellent heat dissipation characteristics, by adding a sediment-forming agent to a mixed solution containing Al and one or more of rare earth metal and alkaline earth metal, drying the prepared coprecipitated substance, nitriding, blending the nitrided material with AlN powder, molding and burning. CONSTITUTION:A mixed solution of a solution containing a rare earth metal or an alkaline earth metal [e.g. aqueous solution of Y(NO3)3] obtained by dissolving nitrate, chloride, etc., of one or more of the rare earth metal and the alkaline earth metal in water or an alcohol and an Al-containing solution (e.g. aqueous solution of AlCl3) having Al corresponding to 2.6-6.0 times the total number of mol. of the metal is mixed with a sediment-forming solution such as NH3 water to give coprecipitated Y hydroxide and Al hydroxide. Then the coprecipitated Y hydroxide and Al hydroxide are separated, dried and nitrided in an N2 or NH3 atmosphere at 1,200-1,700 deg.C to give well dispersed compounded oxynitride (nitride) of submicron class, which is blended with AlN powder, molded and sintered in an N2-containing atmosphere at 1,500-2,100 deg.C.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は窒化アルミニウム焼結体の製造方法に係り、と
りわけ高放熱特性が要求されるセラミック回路基板に適
した窒化アルミニウム焼結体の製造方法に関する。
[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing an aluminum nitride sintered body, and in particular, a method for manufacturing an aluminum nitride sintered body suitable for ceramic circuit boards that require high heat dissipation characteristics. Regarding.

〔従来の技術〕[Conventional technology]

窒化アルミニウム焼結体は、高熱伝導性絶縁材料として
注目され、とりわけ高い放熱特性が要求される回路基板
材料としての応用が期待されている。
Sintered aluminum nitride has attracted attention as a highly thermally conductive insulating material, and is expected to be used as a circuit board material that requires particularly high heat dissipation properties.

一般に窒化アルミニウム焼結体の製造方法としては、窒
化アルミニウム焼結体が難焼結性材料であるため、アル
カリ土類酸化物、希土類酸化物等の焼結助剤を混合、成
形した後、窒素雰囲気中で焼成する方法が行なわれてい
る。
In general, the manufacturing method for aluminum nitride sintered bodies is that since aluminum nitride sintered bodies are difficult to sinter, after mixing and shaping sintering aids such as alkaline earth oxides and rare earth oxides, nitrogen A method of firing in an atmosphere is used.

〔発明が解決しようとする問題点〕[Problem that the invention seeks to solve]

しかしながら、上記の製造方法においては、焼結体の母
材たる窒化アルミニウム粉末中に母材粉末に比して平均
粒径の小さい焼結助剤を均質に分散させることが望まし
いにもかかわらず、母材粉末に比して十分粒径の小さい
助剤粉末が得られない、また、得られたとしても、極め
て凝集しやすく、母材粉末中の均質な分散が得られず、
従ってその焼結体の特性が十分でなく、かつ再現性に劣
るという問題が生じていた。
However, in the above manufacturing method, although it is desirable to homogeneously disperse a sintering aid having a smaller average particle size than the base material powder in the aluminum nitride powder that is the base material of the sintered body, It is not possible to obtain an auxiliary powder with a sufficiently small particle size compared to the base material powder, and even if it is obtained, it is extremely prone to agglomeration and homogeneous dispersion in the base material powder cannot be obtained.
Therefore, there have been problems in that the characteristics of the sintered body are not sufficient and the reproducibility is poor.

〔問題点を解決するための手段〕[Means for solving problems]

本発明者らは、上記問題点を解決するために鋭意検討し
た結果、窒化アルミニウム焼結体の主成分たるアルミニ
ウムと、焼結助剤の成分として希土類元素又はアルカリ
土類金属元素から選ばれた少なくとも一種を含有する混
合溶液を作り、該混合溶液と沈澱形成剤とを混合して共
沈体を形成し、乾燥後、1200℃〜1700℃にて窒
化処理を行なうと、極めて良好に分散したアルミニウム
と焼結助剤成分のサブミクロン級の複合酸窒化物(又は
窒化物)粉末が得られる。この粉末と窒化アルミニウム
粉末とを混合した後、成形、焼成すれば、極めて優れた
熱伝導性を持つ窒化アルミニウム焼結体を得られること
を究明し、本発明を完成した。
As a result of intensive studies to solve the above-mentioned problems, the present inventors found that aluminum, which is the main component of the aluminum nitride sintered body, and rare earth elements or alkaline earth metal elements were selected as the components of the sintering aid. A mixed solution containing at least one type of precipitate was prepared, the mixed solution and a precipitant were mixed to form a coprecipitate, and after drying, a nitriding treatment was performed at 1200°C to 1700°C. A submicron-grade composite oxynitride (or nitride) powder of aluminum and a sintering aid component is obtained. The inventors have discovered that by mixing this powder with aluminum nitride powder, molding and firing, it is possible to obtain an aluminum nitride sintered body with extremely excellent thermal conductivity, and have completed the present invention.

すなわち、本発明は、少なくとも1種の希土類金属また
はアルカリ土類金属とアルミニウムとを含む混合溶液と
沈澱形成剤とを混合して共沈体を形成し、それを乾燥後
、窒化処理して得られる粉末に窒化アルミニウム粉末を
混合し、成形し、窒素雰囲気中で焼成することを特徴と
する窒化アルミニウム焼結体の製造方法にある。
That is, the present invention provides a method of forming a coprecipitate by mixing a mixed solution containing at least one kind of rare earth metal or alkaline earth metal and aluminum with a precipitate, and then drying the co-precipitate and then nitriding the co-precipitate. The present invention provides a method for producing an aluminum nitride sintered body, comprising mixing aluminum nitride powder with the powder, molding, and firing in a nitrogen atmosphere.

希土類金属またはアルカリ土類金属を含む溶液を作成す
るには、これらの金属の硝酸塩、塩化物などを水あるい
はアルコールに溶解するほか、これらの金属を酸の溶液
に直接に溶解させてもよい。
To prepare a solution containing rare earth metals or alkaline earth metals, nitrates, chlorides, etc. of these metals may be dissolved in water or alcohol, or these metals may be directly dissolved in an acid solution.

アルミニウムを含む溶液を作成するにも、同様に、塩化
アルミニウム、硝酸アルミニウム、トリエチルアルミニ
ウム等を水あるいはアルコールに溶解させるほか、金属
アルミニウムを塩酸などの酸に溶解させて水溶液として
もよい、混合溶液中の希土類金属あるいはアルカリ土類
金属(焼結助剤成分)とアルミニウム(母材成分)の比
率は、特に限定されない、共沈体を仮焼してサブミクロ
ン級の焼結助剤成分と母材成分の良く分散した粉末を得
、それを窒化アルミニウム粉末と混合することによって
、窒化アルミニウム粉末と焼結助剤とを単純に混合した
場合よりもより均一に焼結助剤を母材中に分散させるこ
とができ、その結果、高密度で高熱伝導性の窒化アルミ
ニウムが得られるというところに本発明の特徴がある。
Similarly, to create a solution containing aluminum, in addition to dissolving aluminum chloride, aluminum nitrate, triethylaluminum, etc. in water or alcohol, metallic aluminum can also be dissolved in an acid such as hydrochloric acid to create an aqueous solution, or in a mixed solution. The ratio of rare earth metal or alkaline earth metal (sintering aid component) to aluminum (base material component) is not particularly limited. By obtaining a powder with well-dispersed components and mixing it with aluminum nitride powder, the sintering aid is more uniformly dispersed in the base material than when simply mixing the aluminum nitride powder and the sintering aid. The present invention is characterized in that aluminum nitride with high density and high thermal conductivity can be obtained as a result.

従って、混合溶液あるいは共沈体中の希土類金属あるい
はアルカリ土類金属成分に対するアルミニウム成分の混
合比にかかわらず、基本的に本発明の効果は奏せられる
ものである。一般的には、希土類金属あるいはアルカリ
土類金属の合計モル数に対して2.0倍〜6倍のアルミ
ニウムを用いることが好ましい。
Therefore, the effects of the present invention can basically be achieved regardless of the mixing ratio of the aluminum component to the rare earth metal or alkaline earth metal component in the mixed solution or coprecipitate. Generally, it is preferable to use aluminum in an amount of 2.0 to 6 times the total number of moles of rare earth metals or alkaline earth metals.

2、0より小ないと効果が十分でなく、6倍より多くし
ても効果の向上は見込めない。
If it is less than 2.0, the effect will not be sufficient, and if it is more than 6 times, no improvement in the effect can be expected.

沈澱形成剤としては、例えば、アンモニア、炭酸アンモ
ニア、苛性アルカリ、しゆう酸、しゆう酸アンモニウム
、アミン、オキシン等の存機試薬が用いられる。
As the precipitant, for example, a conventional reagent such as ammonia, ammonia carbonate, caustic alkali, oxalic acid, ammonium oxalate, amine, oxine, etc. is used.

混合溶液と沈澱形成剤を混合して共沈を行なわせるには
、沈澱形成剤を溶解した溶液を攪拌しながらそれに前記
混合溶液を徐々に添加して沈澱させる方法が一般的に採
用されるが、これに限定されない。共沈体は、−a的に
、水酸化物の複合体である。
In order to perform coprecipitation by mixing a mixed solution and a precipitate-forming agent, a method is generally adopted in which the mixed solution is gradually added to a solution in which the precipitate-forming agent is dissolved while stirring to cause precipitation. , but not limited to. A coprecipitate is a complex of hydroxides.

得られた共沈体は、分離し、洗浄し、乾燥後、1200
℃〜1700℃で窒化処理を行なう。この窒化処理は典
型的には窒素あるいはアンモニア雰囲気中で行なう、こ
の窒化処理によって共沈体はサブミクロン級の良く分散
された複合酸窒化物ないしは窒化物に変化する。
The obtained coprecipitate was separated, washed, and dried at 1200 °C.
Nitriding treatment is performed at a temperature of 1700°C to 1700°C. This nitriding treatment is typically carried out in a nitrogen or ammonia atmosphere, and the coprecipitate is transformed into a submicron-sized, well-dispersed composite oxynitride or nitride.

次いで、窒化処理した粉末と、窒化アルミニウム粉末と
を混合した後、常法に従って窒素含有雰囲気中1500
〜2100℃で焼結すると所望の窒化アルミニウム焼結
体が得られる。
Next, after mixing the nitrided powder and aluminum nitride powder, the mixture was heated in a nitrogen-containing atmosphere for 1500 min according to a conventional method.
Sintering at ~2100°C yields the desired aluminum nitride sintered body.

〔実施例〕〔Example〕

くスJ[l> 希土類金属のイツトリウムの硝酸塩溶液である硝酸イツ
トリウム水溶液(1,01/sa1濃度)88.56c
cと、アルミニウムの塩化物である塩化アルミニウム水
溶液(1,01/mol濃度) 731.71ccとを
混合した溶液を、6N−アンモニア水51中に徐々に添
加して、Y2OとA13゛の水酸化物共沈体を得た。
Kusu J [l> Yttrium nitrate aqueous solution (1,01/sa1 concentration), which is a nitrate solution of the rare earth metal yttrium, 88.56c
A mixed solution of 731.71 cc of aluminum chloride aqueous solution (1,01/mol concentration), which is a chloride of aluminum, was gradually added to 6N-ammonia water 51 to hydroxylate Y2O and A13'. A coprecipitate was obtained.

この粉末をアンモニア気流中(10It /m1n)に
て1500℃にて4hr加熱し、窒化処理を行なった。
This powder was heated at 1500° C. for 4 hours in an ammonia stream (10 It/m1n) to perform nitriding treatment.

得られた粉末の平均粒径は、0.35μmであった。The average particle size of the obtained powder was 0.35 μm.

この粉末20gと市販のAIN粉末(平均粒径1.3−
am)  85 gをポリポット中にてエタノール20
0ccと共に4hr混合し、乾燥させた後、2.000
kg / cs ”の圧力にて成形し、窒素1ate下
にて1700℃、2hrの条件で焼成を行なった。
20g of this powder and commercially available AIN powder (average particle size 1.3-
am) 85 g in a polypot with 20% ethanol
After mixing with 0cc for 4 hours and drying, 2.000
The molding was carried out under a pressure of "kg/cs" and fired at 1700° C. for 2 hours under 1ate of nitrogen.

得られた焼結体は、室温にて、相対密度99%、熱伝導
率210Wの特性を有していた。
The obtained sintered body had a relative density of 99% and a thermal conductivity of 210 W at room temperature.

く此!> 市販のAIN粉末(平均粒径1.3 p m) 100
gと市販のY!0.粉末(平均粒径1.Oum)5gを
ポリポット中にてエタノール200ccと共に4hr混
合し、乾燥させた後、2000 kg / cm ”の
圧力にて成形し、窒素1at−下にて、1700℃、2
hrの条件で焼成を行なった。
Kukoko! > Commercially available AIN powder (average particle size 1.3 pm) 100
g and commercially available Y! 0. 5 g of powder (average particle size 1.0m) was mixed with 200 cc of ethanol in a polypot for 4 hours, dried, molded at a pressure of 2000 kg/cm'', and heated at 1700°C under 1 atm of nitrogen for 2 hours.
Firing was performed under conditions of hr.

得られた焼結体は、室温にて相対密度98%熱伝導率1
70 Wの特性を有していた。
The obtained sintered body has a relative density of 98% and a thermal conductivity of 1 at room temperature.
It had a characteristic of 70W.

く去m影〉 アルカリ土類金属のカルシウムの硝酸塩溶液である硝酸
カルシウム水溶液(1,01/a+oj!濃度178.
31ccと塩化アルミニウム水溶液(1,01/1lo
l濃度) 731.71ccとを混合した溶液を、6N
−アンモニア水5N中に徐々に添加して、Ca(1とA
I”の水酸化物共沈体を得た。
Calcium nitrate aqueous solution (1,01/a+oj! concentration 178.
31cc and aluminum chloride aqueous solution (1,01/1lo
l concentration) 731.71cc mixed solution with 6N
- Gradually add Ca(1 and A) to 5N ammonia water.
A hydroxide coprecipitate of I'' was obtained.

この粉末をアンモニア気流中(101/win)にて1
500℃にて4hr加熱し、窒化処理を行なった。
This powder was mixed in an ammonia stream (101/win) for 1
Nitriding treatment was performed by heating at 500° C. for 4 hours.

得られた粉末の平均粒径は、0.32μmであった。The average particle size of the obtained powder was 0.32 μm.

この粉末4.0gと市販のAJN粉末(平均粒径1.3
μm)97gをポリポット中にてエタノール200cc
と共に4hr混合し、乾燥させた後、2.000kg 
/ > ”の圧力にて成形し、窒素1atll下にて1
700℃、2hrの条件で焼成を行なった。
4.0 g of this powder and commercially available AJN powder (average particle size 1.3)
μm) 97g in a polypot with 200cc of ethanol
After mixing for 4 hours and drying, 2.000 kg
Molding at a pressure of / > ” and 1 atll under nitrogen
Firing was performed at 700°C for 2 hours.

得られた焼結体は、室温にて、相対密度99%、熱伝導
率190Wの特性を有していた。
The obtained sintered body had a relative density of 99% and a thermal conductivity of 190 W at room temperature.

〈比較IL> 市販のAjlN粉末(平均粒径1.3 μm) 100
 gと市販のCaO粉末1.0g(平均粒径3.0μm
)をポリポット中にてエタノール200ccと共に4h
r混合し、乾燥させた後、2000 ksr / cs
 ”の圧力にて成形し、窒素1ate下にて、1700
℃、2hrの条件で焼成を行なった。
<Comparative IL> Commercially available AjlN powder (average particle size 1.3 μm) 100
g and 1.0 g of commercially available CaO powder (average particle size 3.0 μm
) in a polypot with 200cc of ethanol for 4 hours.
2000 ksr/cs after mixing and drying
Molding at a pressure of 1,700 yen under nitrogen 1ate
Firing was performed at ℃ for 2 hours.

得られた焼結体は、室温にて相対密度98%、熱伝導率
160Wの特性を有していた。
The obtained sintered body had a relative density of 98% and a thermal conductivity of 160 W at room temperature.

〔発明の効果〕〔Effect of the invention〕

本発明の方法によれば、窒化アルミニウム母材粉末中に
サブミクロン級の焼結助剤がより均一に分散されるため
、緻密で高熱伝導性の窒化アルミニウム焼結体が得られ
、放熱特性に優れた回路基板を提供する。
According to the method of the present invention, the submicron-level sintering aid is more uniformly dispersed in the aluminum nitride base material powder, so a dense and highly thermally conductive aluminum nitride sintered body can be obtained, and the heat dissipation properties are improved. Provide superior circuit boards.

Claims (1)

【特許請求の範囲】[Claims] 1、少なくとも1種の希土類金属またはアルカリ土類金
属とアルミニウムとを含む混合溶液と沈澱形成剤とを混
合して共沈体を形成し、それを乾燥後、窒化処理して得
られる粉末に窒化アルミニウム粉末を混合し、成形し、
窒素雰囲気中で焼成することを特徴とする窒化アルミニ
ウム焼結体の製造方法。
1. A mixed solution containing at least one kind of rare earth metal or alkaline earth metal and aluminum is mixed with a precipitate forming agent to form a coprecipitate, and after drying, the resulting powder is nitrided. Mix aluminum powder, form it,
A method for producing an aluminum nitride sintered body, which comprises firing in a nitrogen atmosphere.
JP62127204A 1987-05-26 1987-05-26 Method for manufacturing aluminum nitride sintered body Expired - Lifetime JP2548192B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP62127204A JP2548192B2 (en) 1987-05-26 1987-05-26 Method for manufacturing aluminum nitride sintered body

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP62127204A JP2548192B2 (en) 1987-05-26 1987-05-26 Method for manufacturing aluminum nitride sintered body

Publications (2)

Publication Number Publication Date
JPS63291878A true JPS63291878A (en) 1988-11-29
JP2548192B2 JP2548192B2 (en) 1996-10-30

Family

ID=14954292

Family Applications (1)

Application Number Title Priority Date Filing Date
JP62127204A Expired - Lifetime JP2548192B2 (en) 1987-05-26 1987-05-26 Method for manufacturing aluminum nitride sintered body

Country Status (1)

Country Link
JP (1) JP2548192B2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012053595A1 (en) * 2010-10-20 2012-04-26 三菱化学株式会社 Method for producing nitride fluophor by using coprecipitated material, nitride fluophor, and material therefor
CN114804887A (en) * 2022-03-22 2022-07-29 武汉科技大学 (CoCrFeMnNi) N high-entropy ceramic powder and preparation method thereof

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS54138899A (en) * 1978-04-21 1979-10-27 Toshiba Corp Production of silicon nitridg base powder
JPS6221764A (en) * 1985-07-18 1987-01-30 住友電気工業株式会社 Manufacture of aluminum nitride
JPS6270210A (en) * 1985-09-24 1987-03-31 Natl Inst For Res In Inorg Mater Production of aluminum nitride-silicon carbide composite fine powder
JPS6270209A (en) * 1985-09-24 1987-03-31 Natl Inst For Res In Inorg Mater Production of readily sintered beta-sialon based fine powder
JPS62252373A (en) * 1986-04-24 1987-11-04 株式会社村田製作所 Manufacture of aluminum nitride sintered body

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS54138899A (en) * 1978-04-21 1979-10-27 Toshiba Corp Production of silicon nitridg base powder
JPS6221764A (en) * 1985-07-18 1987-01-30 住友電気工業株式会社 Manufacture of aluminum nitride
JPS6270210A (en) * 1985-09-24 1987-03-31 Natl Inst For Res In Inorg Mater Production of aluminum nitride-silicon carbide composite fine powder
JPS6270209A (en) * 1985-09-24 1987-03-31 Natl Inst For Res In Inorg Mater Production of readily sintered beta-sialon based fine powder
JPS62252373A (en) * 1986-04-24 1987-11-04 株式会社村田製作所 Manufacture of aluminum nitride sintered body

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012053595A1 (en) * 2010-10-20 2012-04-26 三菱化学株式会社 Method for producing nitride fluophor by using coprecipitated material, nitride fluophor, and material therefor
CN114804887A (en) * 2022-03-22 2022-07-29 武汉科技大学 (CoCrFeMnNi) N high-entropy ceramic powder and preparation method thereof

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JP2548192B2 (en) 1996-10-30

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