JP2742599B2 - Aluminum nitride sintered body and method for producing the same - Google Patents
Aluminum nitride sintered body and method for producing the sameInfo
- Publication number
- JP2742599B2 JP2742599B2 JP1098496A JP9849689A JP2742599B2 JP 2742599 B2 JP2742599 B2 JP 2742599B2 JP 1098496 A JP1098496 A JP 1098496A JP 9849689 A JP9849689 A JP 9849689A JP 2742599 B2 JP2742599 B2 JP 2742599B2
- Authority
- JP
- Japan
- Prior art keywords
- metal
- weight
- sintered body
- aluminum nitride
- less
- 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.)
- Expired - Fee Related
Links
Landscapes
- Ceramic Products (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、窒化アルミニウム質焼結体およびその製造
方法に関し、より詳細には高熱伝導性を有し、放熱性の
基板等の電子部品材料に好適な窒化アルミニウム質焼結
体およびその製造方法に関する。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aluminum nitride sintered body and a method for producing the same, and more particularly, to a material for electronic components such as a substrate having high thermal conductivity and heat dissipation. The present invention relates to a suitable aluminum nitride sintered body and a method for producing the same.
近時、情報処理装置の高性能化、高速化に伴いそれを
構成する半導体集積回路も高密度化、高集積化が急速に
進み、そのために半導体集積回路素子の大電力化により
該素子の発熱量が著しく増加し、前記半導体集積回路素
子を正常に且つ安定に作動させるためには、その発生す
る熱をいかに効率よく除去するかが課題となっている。In recent years, as information processing devices have become higher in performance and higher in speed, the density of semiconductor integrated circuits constituting the information processing devices has also increased rapidly, and the integration thereof has rapidly advanced. In order to operate the semiconductor integrated circuit device normally and stably, there is a problem how to efficiently remove the generated heat.
そこで、従来のアルミナを基体とする半導体パッケー
ジ等では熱伝導率が低く放熱が不充分であることから、
熱伝導率が高いセラミック材料として酸化ベリリウム質
焼結体が提案されているが、その毒性の点で使用上難点
があった。Therefore, conventional semiconductor packages based on alumina have low thermal conductivity and insufficient heat dissipation.
A beryllium oxide sintered body has been proposed as a ceramic material having a high thermal conductivity, but has a problem in use due to its toxicity.
そのため、酸化ベリリウム焼結体に代わる高熱伝導性
基板材料として常温から高温まで高い機械的強度を有
し、電気絶縁性が高く、高熱伝導率性であり、熱膨張係
数がアルミナに比べシリコン単結晶に近いなどの優れた
特性を有する、窒化アルミニウム質焼結体が注目されて
いる。For this reason, it has high mechanical strength from room temperature to high temperature, high electrical insulation, high thermal conductivity, and a single crystal silicon that has a higher thermal expansion coefficient than alumina as a high thermal conductive substrate material that replaces beryllium oxide sintered body. Attention has been focused on aluminum nitride-based sintered bodies having excellent properties such as those close to.
しかしながら、窒化アルミニウムは本来難焼結性であ
り、単味では高い熱伝導率を有する高密度の焼結体を得
ることが困難であった。そこで、窒化アルミニウム原料
粉末に焼結助剤として周期律表II a族元素もしくはIII
a族元素の化合物、例えばカルシウム、ストロンチウ
ム、バリウム等のアルカリ土類金属もしくはイットリウ
ム及び希土類元素の化合物を添加して焼結体を得ること
が行われている。However, aluminum nitride is inherently difficult to sinter, and it was difficult to obtain a high-density sintered body having high thermal conductivity simply. Therefore, aluminum nitride raw material powder is used as a sintering aid
A sintered body is obtained by adding a compound of a group a element, for example, an alkaline earth metal such as calcium, strontium and barium, or a compound of yttrium and a rare earth element.
しかしながら、従来の方法では窒化アルミニウム質焼
結体の粒界相に存在する焼結助剤成分の量の不均一が生
じ、高熱伝導性の材料を容易に且つ安定に製造すること
が困難であった。また、同時に粒界相の不均一に起因
し、基板などに用いた場合、メタライズ性の不良や長期
信頼性が低下するという問題があった。However, in the conventional method, the amount of the sintering aid component present in the grain boundary phase of the aluminum nitride sintered body is not uniform, and it is difficult to easily and stably produce a material having high thermal conductivity. Was. At the same time, due to the non-uniformity of the grain boundary phase, when used for a substrate or the like, there is a problem that the metallization property is poor and the long-term reliability is reduced.
このような傾向は焼結助剤として一般的に用いられて
いるY2O3において、特に顕著に観察される。これは、焼
結助剤が窒化アルミニウムに含まれる酸化物相と反応し
て粒界相を形成し、窒化アルミニウムの焼結を促進する
が、焼成を終了した後も、粒界相に存在しているためで
あり、その結果、焼結体において、色むら、しみ等の発
生、熱伝導率の局所的不均一などの問題を生じ、容易に
且つ安定して製造することができないという問題点を有
していた。Such a tendency is particularly remarkably observed in Y 2 O 3 which is generally used as a sintering aid. This is because the sintering aid reacts with the oxide phase contained in the aluminum nitride to form a grain boundary phase and promotes sintering of the aluminum nitride. As a result, in the sintered body, there occur problems such as generation of color unevenness, spots, etc., and local nonuniformity of thermal conductivity, which makes it difficult to manufacture easily and stably. Had.
そこで、１つの対策として、焼結助剤の量を極力へら
し、粒界相を減らすことが考ええられるが、焼結助剤は
窒化アルミニウムを焼結させるために不可欠の要素であ
るため、焼結助剤の量が少なすぎると、高密度の焼結体
を得ることができないという問題があった。Therefore, as one measure, it is conceivable to reduce the grain boundary phase by reducing the amount of the sintering aid as much as possible. However, since the sintering aid is an indispensable element for sintering aluminum nitride, If the amount of the binder is too small, there is a problem that a high-density sintered body cannot be obtained.
そこで本発明者は先に、焼結体中の残存粒界相量およ
び不均一性に対し、窒化アルミニウムの焼結温度におい
て用いる焼結助剤の蒸発率が大きく関与していることを
知見し、焼結助剤として1900℃の温度における蒸発率が
10-6〜10-3g/cm2・secの範囲にある金属あるいは金属化
合物を用い、この焼結助剤を焼成時、焼結に必要とされ
る十分な液相を生成し得る量で配合すると同時に、焼成
工程中にその焼結助剤を揮散させることによって、最終
焼結体中の粒界相を極力低減しせめると同時に粒界相の
不均一性をほとんど皆無となし、かつ高密度化、高熱伝
導率化が達成できることを見出したが、その熱伝導率は
たかだか200W/m・Ｋであった。Therefore, the present inventor has previously found that the evaporation rate of the sintering aid used at the sintering temperature of aluminum nitride has a large effect on the amount and non-uniformity of the residual grain boundary phase in the sintered body. The evaporation rate at a temperature of 1900 ° C as a sintering aid
Using a metal or metal compound is in the range of 10 -6 ~10 -3 g / cm 2 · sec, when firing the sintering aid, an amount capable of producing sufficient liquid phase required for sintering Simultaneously with the compounding, the sintering aid is volatilized during the firing step, so that the grain boundary phase in the final sintered body is reduced as much as possible, and at the same time, the non-uniformity of the grain boundary phase is almost completely eliminated. It was found that density and high thermal conductivity could be achieved, but the thermal conductivity was at most 200 W / m · K.
本発明は上記問題点を解決することを主たる目的とす
るものであり、具体的には、高熱伝導性および高密度の
均一質な窒化アルミニウム質焼結体を提供することにあ
り、他の目的は該焼結体を容易に且つ安定に製造するた
めの方法を提供することにある。An object of the present invention is to solve the above-mentioned problems, and specifically, to provide a uniform aluminum nitride sintered body having high thermal conductivity and high density. An object of the present invention is to provide a method for easily and stably producing the sintered body.
本発明者等は上記問題点に対し、研究を重ねた結果、
焼結体中の残存粒界相量および不均一性に対し、窒化ア
ルミニウムの焼結温度において用いる焼結助剤の蒸発率
が大きく関与していること、熱伝導率の向上にはアルカ
リ土類金属化合物を同時に添加すればよいことを知見し
た。そこで焼結助剤として1900℃の温度における蒸発率
が10-6〜10-3g/cm2・secの範囲にある金属あるいは金属
化合物とアルカリ土類金属あるいはその金属化合物を用
い、この焼結助剤を焼成時、焼結に必要とされる十分な
液相を生成し得る量で配合すると同時に、焼成工程中に
その焼結助剤を揮散させることによって最終焼結体中の
粒界相を極力低減させめると同時に粒界相の不均一をほ
とんど皆無となし、かつ高密度化、高熱伝導率化が達成
できることを見出した。The present inventors have conducted studies on the above problems, and as a result,
The evaporation rate of the sintering aid used at the sintering temperature of aluminum nitride greatly affects the amount and non-uniformity of the residual grain boundary phase in the sintered body. It has been found that a metal compound may be added simultaneously. So using the evaporation rate at a temperature of 1900 ° C. as the sintering aid is 10 -6 ~10 -3 g / cm metal or metal compound is in the range of 2 · sec and an alkaline earth metal or a metal compound, the sintering At the time of firing, the auxiliary is mixed in an amount capable of producing a sufficient liquid phase required for sintering, and at the same time, the sintering aid is volatilized during the firing step, thereby forming a grain boundary phase in the final sintered body. Was found to be as small as possible, and at the same time, the grain boundary phase was almost completely non-uniform, and it was possible to achieve a high density and a high thermal conductivity.
即ち、本発明は、AlN粉末を84〜97重量％と、1900℃
における蒸発率が10-6〜10-3g/cm2・secの範囲にある希
土類金属としてイッテリビウム（Yb）あるいはその金属
化合物粉末を３〜15重量％の割合で含有し、且つアルカ
リ土類金属としてカルシウム（Ca）あるいはその金属化
合物粉末を0.01〜0.2重量％の割合で含有してなる混合
物を成形後、窒素ガスを1Torr以上含有する非酸化性雰
囲気下、1700〜2000℃の温度で焼成して、前記イッテリ
ビウムあるいは金属化合物を焼結体中の含有量が金属に
換算して0.1重量％以下、カルシウムあるいはその金属
化合物が金属に換算して0.05重量％以下になるまで揮散
させることによって、密度3.2〜3.3g/cm3、熱伝導率200
W/m・Ｋ以上の窒化アルミニウム質焼結体を得ることが
できるというものである。That is, according to the present invention, AlN powder is added at 84 to 97% by weight,
Contains 3 to 15% by weight of ytterbium (Yb) or a metal compound powder thereof as a rare earth metal having an evaporation rate in the range of 10 -6 to 10 -3 g / cm 2 · sec, and an alkaline earth metal After forming a mixture containing calcium (Ca) or its metal compound powder at a ratio of 0.01 to 0.2% by weight, the mixture is fired at a temperature of 1700 to 2000 ° C. in a non-oxidizing atmosphere containing 1 Torr or more of nitrogen gas. The volatilization of the ytterbium or the metal compound until the content in the sintered body becomes 0.1% by weight or less in terms of metal and calcium or its metal compound becomes 0.05% by weight or less in terms of metal, whereby the density is reduced. 3.2~3.3g / cm 3, the thermal conductivity 200
An aluminum nitride sintered body of W / m · K or more can be obtained.
以下、本発明を詳述する。 Hereinafter, the present invention will be described in detail.
本発明における大きな特長は焼結助剤として1900℃に
おける蒸発率（Evaporatoin rate）が10-6〜10-3g/cm2
・sec、特に10-5〜10-4g/cm2・secの範囲にある希土類
金属あるいはその金属化合物とアルカリ土類金属あるい
はその金属化合物を同時に用いる点にある。該金属化合
物としてはYb2O3が挙げられ、またアルカリ土類金属化
合物としてはCaOが挙げられる。蒸発率はBalkevich等の
文献（Inorg.Mat.11（７）,12（１））に記載されるよ
うに真空中における物質の焼結体から得られたデータで
ある。文献によれば1900℃における蒸発率はYb2O3が2.3
×10-5g/cm2・secであるのに対し、通常使用されるY2O3
は8.0×10-8g/cm2・secと小さい値を示す。A major feature of the present invention is that the sintering aid has an evaporation rate at 1900 ° C. of 10 −6 to 10 −3 g / cm 2.
Sec, in particular, a rare earth metal or its metal compound and an alkaline earth metal or its metal compound in the range of 10 -5 to 10 -4 g / cm 2 · sec. The metal compound includes Yb 2 O 3 , and the alkaline earth metal compound includes CaO. The evaporation rate is data obtained from a sintered body of a substance in a vacuum as described in Balkevich et al. (Inorg. Mat. 11 (7), 12 (1)). According to the literature, the evaporation rate at 1900 ° C is 2.3% for Yb 2 O 3.
× 10 -5 g / cm to which the a 2 · sec, Y 2 O 3 usually used
Shows a small value of 8.0 × 10 −8 g / cm 2 · sec.
一方、本発明において使用される窒化アルミニウム粉
末は直接窒化法、アルミナ還元法等、公知の方法で製造
されたもので酸素含有量1.5重量％以下、炭素含有量0.1
5重量％以下、アルミニウムを除く陽イオン不純物含有
量0.1重量％以下、特にSi含有量およびFeの含有量が共
に100ppm以下の平均粒径２μｍ以下の粉末である。On the other hand, the aluminum nitride powder used in the present invention is manufactured by a known method such as a direct nitriding method or an alumina reduction method, and has an oxygen content of 1.5% by weight or less and a carbon content of 0.1% or less.
It is a powder having an average particle diameter of 2 μm or less in which the content of cationic impurities excluding aluminum is 0.1% by weight or less, particularly the content of both Si and Fe is 100 ppm or less.
窒化アルミニウム粉末および焼結助剤は、焼成におい
て、焼結助剤が、液相を十分に生成し得る量で配合さ
れ、窒化アルミニウム粉末84〜97重量％、希土類金属あ
るいはその金属化合物３〜15重量％、且つアルカリ土類
金属あるいはその金属化合物粉末を0.01〜0.2重量％の
割合で配合される。The aluminum nitride powder and the sintering aid are mixed in such an amount that the sintering aid can sufficiently form a liquid phase in firing, and the aluminum nitride powder is 84 to 97% by weight, the rare earth metal or its metal compound 3 to 15%. % By weight, and an alkaline earth metal or its metal compound powder in an amount of 0.01 to 0.2% by weight.
配合された粉末は、所望により、有機溶媒中で混合さ
れる。この時、有機溶媒中に含有される水分量は0.4重
量％以下に設定される。これにより、AlN粉末の分散性
を向上させるとともに、溶媒中の水分との反応によって
AlN粒子表面の酸化をを防止することができる。The compounded powder is mixed in an organic solvent, if desired. At this time, the amount of water contained in the organic solvent is set to 0.4% by weight or less. As a result, the dispersibility of the AlN powder is improved, and the reaction with water in the solvent
Oxidation of the AlN particle surface can be prevented.
得られた混合粉末は公知の成形手段、例えば金型もし
くは静水圧を用いたプレス成形、シート成形、押し出し
成形等により所望の形状に形成した後、焼成に移され
る。The obtained mixed powder is formed into a desired shape by known molding means, for example, press molding using a mold or hydrostatic pressure, sheet molding, extrusion molding, etc., and then is transferred to firing.
焼成は、窒素ガスを1Torr以上、特に760Torr以上含有
する非酸化性雰囲気で1700〜2000℃の焼成温度で焼成さ
れる。焼成手段としては、常圧焼成、窒素ガス圧焼成が
挙げられ、さらにこれらの焼成によって得られた焼結体
中の前記希土類金属あるいはその金属化合物が金属に換
算して0.1重量％以下、アルカリ土類金属あるいはその
金属化合物が金属に換算して0.05重量％以下含有する焼
結体を熱間静水圧焼成することにより、緻密化を促進す
ることができる。The firing is performed at a firing temperature of 1700 to 2000 ° C. in a non-oxidizing atmosphere containing nitrogen gas at 1 Torr or more, particularly 760 Torr or more. Examples of the firing means include normal pressure firing and nitrogen gas pressure firing. Further, the rare earth metal or its metal compound in the sintered body obtained by firing is 0.1% by weight or less in terms of metal, and Densification can be promoted by hot isostatic sintering of a sintered body containing 0.05% by weight or less of the metal or its metal compound in terms of metal.
本発明によれば、焼成工程において、1200℃から焼成
温度までの昇温速度を平均40℃/min以下に設定し、焼結
が進行し始める前に、成形体中に焼結助剤と窒化アルミ
ニウム粉末表面の酸素との反応により液相成分としてア
ルミネートを均一に生成させておくことが望ましく、昇
温速度が平均40℃/minを超えると液相成分であるアルミ
ネートが十分な生成されないまま、焼成温度に到達し、
焼結助剤が揮散してしまい、十分な焼結が進行せず、高
密度の焼結体が得られなくなる。According to the present invention, in the firing step, the rate of temperature increase from 1200 ° C. to the firing temperature is set to an average of 40 ° C./min or less, and the sintering aid and the nitriding It is desirable to uniformly generate aluminate as a liquid phase component by reaction with oxygen on the surface of the aluminum powder, and if the temperature rise rate exceeds an average of 40 ° C./min, the aluminate that is a liquid phase component is not generated sufficiently. As it reaches the firing temperature,
The sintering aid volatilizes, and sufficient sintering does not proceed, so that a high-density sintered body cannot be obtained.
十分にアルミネートが生成した状態で焼結が進行する
と同時に、焼結助剤の揮散が徐々に進行する。この時、
焼結が十分に進行するまで、液相成分を残留させておく
ために、例えば焼成炉内に成形体中の焼結助剤と同一の
助剤粉末を設置しておくことによって、成形体のまわり
を助剤の蒸気圧とほぼ同一にしておき、焼成が十分に進
行したのち、焼成炉のガスを強制的に置換し、成形体の
まわりを助剤の上記圧より低く保つことにって助剤の揮
散を促進することができる。At the same time as sintering proceeds while aluminate is sufficiently generated, volatilization of the sintering aid gradually proceeds. At this time,
In order to keep the liquid phase component until sintering proceeds sufficiently, for example, by installing the same auxiliary powder as the sintering aid in the molded body in a firing furnace, By keeping the surroundings almost the same as the vapor pressure of the auxiliary, and after the firing has sufficiently proceeded, the gas in the firing furnace is forcibly replaced to keep the surroundings of the molded body lower than the above-mentioned pressure of the auxiliary. The volatilization of the auxiliary can be promoted.
しかしながら、蒸気圧による揮散制御では、揮散速度
が遅いために焼成時間を長くする必要があるため、好適
には雰囲気中に炭素を含有させることにより揮散をより
促進することができる。However, in the volatilization control based on the vapor pressure, the volatilization speed is slow, so that it is necessary to lengthen the calcination time. Therefore, the volatilization can be further promoted by preferably containing carbon in the atmosphere.
焼成工程において、最終的に焼成助剤の量がYb金属換
算で0.1重量％以下、好ましくは0.07重量％以下、さら
に好ましくは0.04重量％以下になるまで、また、Ca金属
換算で0.05重量％以下、好ましくは0.03重量％以下、さ
らに好ましくは0.01重量％以下になるまで揮散させる。In the sintering step, the amount of the sintering aid finally becomes 0.1% by weight or less in terms of Yb metal, preferably 0.07% by weight or less, more preferably 0.04% by weight or less, and 0.05% by weight or less in terms of Ca metal. , Preferably 0.03% by weight or less, more preferably 0.01% by weight or less.
焼成終了後は、焼成温度から、1200℃まで平均40℃/m
in以下の速度で降温することが望ましく、それによって
焼結体表面の不均一層を皆無となし、均一化を図ること
ができる。After firing, average 40 ° C / m from firing temperature to 1200 ° C
It is desirable to lower the temperature at a rate of not more than in, thereby eliminating any non-uniform layer on the surface of the sintered body and achieving uniformity.
このような製造方法によって、最終焼結体において、
密度3.2〜3.3g/cm3特に3.24〜3.27g/cm3、熱伝導率200W
/m・Ｋ以上が達成される。By such a manufacturing method, in the final sintered body,
Density 3.2~3.3g / cm 3 particularly 3.24~3.27g / cm 3, the thermal conductivity of 200W
/ mK or more is achieved.
しかしながら、いくら蒸発率の高い助剤を用いても焼
成において揮散を抑えるような焼成を行うと、密度が見
掛け理論密度（焼結体の各原料粉末の密度と配合比率か
ら計算した値）に近い値となり焼結体中の残存助剤が多
く、熱伝導率が高くならない。However, when calcination is performed to suppress volatilization in calcination even if an auxiliary agent having a high evaporation rate is used, the density is close to the apparent theoretical density (a value calculated from the density and the mixing ratio of each raw material powder of the sintered body). Value, and there are many residual assistants in the sintered body, and the thermal conductivity does not increase.
なお、焼結体中の残存する助剤の量をYb金属換算で0.
1重量％以下、Ca金属換算で0.05重量％以下に限定した
理由は、残存助剤量がYb金属換算で0.1重量％を超え、C
a金属換算で0.05重量％を超えると熱伝導率200W/m・Ｋ
が達成されず、また、焼結体が不均一となるからであ
る。また、密度が3.2g/cm3より小さいものは空孔が多
く、3.3/cm3より大きいものは粒界相が多いことを意味
するものである。Incidentally, the amount of the auxiliary agent remaining in the sintered body is calculated as 0.
The reason for limiting the amount to 1% by weight or less and 0.05% by weight or less in terms of Ca metal is that the amount of the remaining auxiliary exceeds 0.1% by weight in terms of Yb metal and C
aIf the metal content exceeds 0.05% by weight, the thermal conductivity is 200W / m ・ K
Is not achieved, and the sintered body becomes non-uniform. Further, those having a density of less than 3.2 g / cm 3 have many vacancies, and those having a density of more than 3.3 / cm 3 mean that there are many grain boundary phases.
また、上記の本発明の構成において、焼結助剤の1900
℃における蒸発率が10-6g/cm2・secを下回ると焼結が進
行した後も焼結体中に粒界相として残存し、色むら、し
み、熱伝導率の局所的不均一の原因となる。また10-3g/
cm2・secを超えると窒化アルミニウムの焼結が十分に進
行する前に助剤成分が蒸発してしまい、緻密化が行われ
なくなる。Further, in the above configuration of the present invention, the sintering aid 1900
If the evaporation rate at 10 ° C is lower than 10 -6 g / cm 2 · sec, it remains as a grain boundary phase in the sintered body even after sintering has progressed, resulting in uneven color, spots, and local unevenness in thermal conductivity. Cause. Also 10 -3 g /
If it exceeds cm 2 · sec, the auxiliary component will evaporate before sintering of aluminum nitride sufficiently proceeds, and densification will not be performed.
さらに、焼結助剤の配合量をYb金属あるいはその金属
化合物粉末を３〜15重量％、Ca金属あるいはその金属化
合物粉末を0.01〜0.2重量％に限定したのは、Yb金属化
合物量が３重量％を下回ると、Ca金属化合物量を多くし
ても焼結体の十分な緻密化が達成されず、15重量％を超
えると助剤の揮散が困難となり、粒界相が多量に残存
し、熱伝導率が低下し、不均一な焼結体になるためであ
り、Ca金属化合物量が0.01を下回ると熱伝導率が200W/m
・Ｋを下回り、0.2重量％を超えると熱伝導率の向上は
見られないからである。Further, the amount of the sintering aid was limited to 3 to 15% by weight of the Yb metal or its metal compound powder and to 0.01 to 0.2% by weight of the Ca metal or its metal compound powder, because the amount of the Yb metal compound was 3% by weight. %, The sintered body cannot be sufficiently densified even if the amount of the Ca metal compound is increased. If the amount exceeds 15% by weight, volatilization of the auxiliary agent becomes difficult, and a large amount of the grain boundary phase remains. This is because the thermal conductivity decreases, resulting in a non-uniform sintered body.If the amount of the Ca metal compound is less than 0.01, the thermal conductivity becomes 200 W / m.
-If it is lower than K and exceeds 0.2% by weight, no improvement in thermal conductivity is observed.
なお、焼結助剤の添加に際しては、Yb2O3、CaOの他に
焼成によってこれらの酸化物に変換し得る炭酸塩や硝酸
塩あるいはYb2O3とCaOとの複合酸化物等の形態で添加し
ても良い。In addition, when adding the sintering aid, in addition to Yb 2 O 3 , CaO, in the form of carbonates or nitrates which can be converted to these oxides by calcination or in the form of a composite oxide of Yb 2 O 3 and CaO It may be added.
以下、本発明を次の例で説明する。 Hereinafter, the present invention will be described with reference to the following examples.
まず、酸素含有量1.5重量％以下、炭素含有量0.15重
量％以下、アルミニウムを除く陽イオン不純物含有量0.
1重量％以下の市販の窒化アルミニウム原料粉末と、Yb2
O3とCaCO3を第１表に示す割合で添加量を変えて混合し
た。次いでこの混合粉末を室温で1000Kg/cm2の圧力を加
えて成形体とした。この成形体を炭素を含有した窒素ガ
ス雰囲気下、1900℃で常圧焼結した。焼成は、1200℃か
ら各焼成温度まで20℃/minの昇温速度で昇温した。First, the oxygen content is 1.5% by weight or less, the carbon content is 0.15% by weight or less, and the content of cationic impurities excluding aluminum is 0.1%.
1% by weight or less of a commercially available aluminum nitride raw material powder and Yb 2
O 3 and CaCO 3 were mixed in the proportions shown in Table 1 while changing the amount of addition. Next, a pressure of 1000 kg / cm 2 was applied to this mixed powder at room temperature to obtain a molded body. This compact was sintered under a normal pressure at 1900 ° C. in a nitrogen gas atmosphere containing carbon. In the firing, the temperature was raised from 1200 ° C. to each firing temperature at a rate of 20 ° C./min.
なお、この昇温速度で、いずれのサンプルもAl2O3と
の反応物（アルミネート）が生成していることを確認し
た。焼成温度到達後は常に窒素ガスを置換した状態で焼
成した。また、1200℃までの降温速度はいずれもは20℃
/minに設定した。但し、No.16は焼成炉内の雰囲気中に
炭素を含有させずに焼成した。こうして、得られた窒化
アルミニウム質焼結体の密度をアルキメデス法で、熱伝
導率をレーザーフラッシュ法で、色むら、しみの発生率
を双眼鏡顕微鏡による目視により、測定、選別を行った
結果を第１表に示す。At this heating rate, it was confirmed that a reaction product (aluminate) with Al 2 O 3 was generated in each sample. After reaching the firing temperature, the firing was always performed with the nitrogen gas replaced. In addition, the rate of cooling down to 1200 ° C is 20 ° C
/ min. However, No. 16 was fired without containing carbon in the atmosphere in the firing furnace. The density and the thermal conductivity of the obtained aluminum nitride sintered body were measured and sorted by the Archimedes method, the thermal conductivity was measured by the laser flash method, and the occurrence rate of color unevenness and spots was visually observed with a binocular microscope. The results are shown in Table 1.
また、焼結体中の助剤量（金属換算量）をICP発光分
光分析法によって測定した。結果は第１表に示した。In addition, the amount of the assistant (metal equivalent) in the sintered body was measured by ICP emission spectroscopy. The results are shown in Table 1.
第１表の結果から明らかなように1900℃の蒸発率が10
-6g/cm2・secを下回るY2O3を用いたNo.17、18の試料で
は、いずれも密度は高いものの、助剤が2.0重量％以上
残存しており、色むら、しみの発生がひどいものであ
り、熱伝導率も低い。 As is clear from the results in Table 1, the evaporation rate at 1900 ° C was 10
In the samples of Nos. 17 and 18 using Y 2 O 3 of less than -6 g / cm 2 · sec, although the density was high, the auxiliary agent remained at 2.0% by weight or more, and the color unevenness and stain The generation is severe and the thermal conductivity is low.
Yb2O3の添加量が３重量％を下回るNo.1の試料では焼
結が不十分となり、高熱伝導率は達成されなかった。ま
た、添加量が15重量％を超えるNo.7の試料では、助剤の
残存量が多く、色むら、しみの発生があった。添加量が
３〜15重量％の範囲中であっても、揮散を抑制したNo.1
6の試料では助剤の残存量が0.1重量％を超え、高熱伝導
率が得られなかった。In the sample of No. 1 in which the addition amount of Yb 2 O 3 was less than 3% by weight, sintering was insufficient, and high thermal conductivity was not achieved. In addition, in the sample of No. 7 in which the addition amount exceeded 15% by weight, the remaining amount of the auxiliary agent was large, and color unevenness and spotting occurred. No. 1 which suppressed volatilization even when the amount of addition was in the range of 3 to 15% by weight.
In the sample of No. 6, the residual amount of the auxiliary exceeded 0.1% by weight, and high thermal conductivity was not obtained.
CaCO3の添加量が0.01重量％を下回るNo.8,9の試料で
は高熱伝導率は達成されなかった。また添加量が0.2重
量％を超えるNo.15の試料では熱伝導率の向上は見られ
なかった。High thermal conductivity was not achieved in the samples Nos. 8 and 9 in which the amount of CaCO 3 added was less than 0.01% by weight. Further, in the sample of No. 15 in which the addition amount exceeded 0.2% by weight, no improvement in the thermal conductivity was observed.
これに対し、本発明の試料No.2〜6,10〜14はいずれも
見掛け密度3.2〜3.3g/cm3、熱伝導率20W/m・Ｋ以上で、
色むら、しみは発生しなかった。In contrast, Samples Nos. 2 to 6 , 10 to 14 of the present invention all had an apparent density of 3.2 to 3.3 g / cm 3 and a thermal conductivity of 20 W / mK or more.
No color unevenness or spotting occurred.
（発明の効果） 以上、詳述した通り、本発明の窒化アルミニウム質焼
結体は、高密度で熱伝導体に優れ、熱的特性、電気的特
性、機械的特性も良好であり、原料コストも低く材料内
での特性の不均一がなく容易に且つ安定して製造できる
ため、電子部品を搭載する絶縁性基板等電子部品材料と
して多くの利点を有する。(Effects of the Invention) As described above in detail, the aluminum nitride sintered body of the present invention has a high density, is excellent in heat conductor, has good thermal properties, electrical properties, and mechanical properties, and has a low raw material cost. Since it can be manufactured easily and stably without the characteristic unevenness in the material, it has many advantages as an electronic component material such as an insulating substrate on which the electronic component is mounted.
Claims (3)
b）金属あるいはその金属化合物とカルシウム（Ca）金
属あるいはその金属化合物を主成分としてなり、該Yb金
属あるいはその金属化合物が金属に換算して0.1重量％
以下、Ca金属あるいはその金属化合物が金属に換算して
0.05重量％以下の割合で含有された密度3.2〜3.3g/c
m3、熱伝導率200W/m・Ｋ以上の窒化アルミニウム質焼結
体。(1) AlN and ytterbium (Y
b) A metal or its metal compound and calcium (Ca) metal or its metal compound as main components, and the Yb metal or its metal compound is 0.1% by weight in terms of metal.
Below, Ca metal or its metal compound is converted to metal
Density 3.2-3.3g / c contained at a ratio of 0.05% by weight or less
Aluminum nitride sintered body with m 3 and thermal conductivity of 200 W / m · K or more.
〜15重量％の割合で且つ、CaO粉末を0.01〜0.2重量％の
割合で含有してなる混合物を成形後、窒素ガスを1Torr
以上含有する非酸化性雰囲気下、1700〜2000℃の温度で
焼成して、Yb金属あるいはその金属化合物を焼結体中の
含有量が金属に換算して0.1重量％以下、Ca金属あるい
はその金属化合物が金属に換算して0.05重量％以下にな
るまで揮散させることを特徴とする窒化アルミニウム質
焼結体の製造方法。2. An AlN powder of 84 to 97% by weight and a Yb 2 O 3 powder of 3%
After molding a mixture containing CaO powder at a ratio of 0.01 to 0.2% by weight and a nitrogen gas at a pressure of 1 Torr.
Baking at a temperature of 1700 to 2000 ° C under a non-oxidizing atmosphere containing above, the content of Yb metal or its metal compound in the sintered body is 0.1% by weight or less in terms of metal, Ca metal or its metal A method for producing an aluminum nitride-based sintered body, wherein the compound is volatilized until it becomes 0.05% by weight or less in terms of metal.
請求の範囲第２項記載の窒化アルミニウム質焼結体の製
造方法。3. The method according to claim 2, wherein carbon is contained in a non-oxidizing atmosphere.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1098496A JP2742599B2 (en) | 1989-04-18 | 1989-04-18 | Aluminum nitride sintered body and method for producing the same |
| US07/824,681 US5250478A (en) | 1988-07-28 | 1992-01-17 | Aluminum nitride sintered body and process for preparation thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1098496A JP2742599B2 (en) | 1989-04-18 | 1989-04-18 | Aluminum nitride sintered body and method for producing the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02279567A JPH02279567A (en) | 1990-11-15 |
| JP2742599B2 true JP2742599B2 (en) | 1998-04-22 |
Family
ID=14221253
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1098496A Expired - Fee Related JP2742599B2 (en) | 1988-07-28 | 1989-04-18 | Aluminum nitride sintered body and method for producing the same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2742599B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4939932B2 (en) | 2004-03-29 | 2012-05-30 | 電気化学工業株式会社 | Aluminum nitride powder and method for producing the same |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6416361A (en) * | 1987-07-10 | 1989-01-19 | Matsushita Electric Ind Co Ltd | Grinding device |
| JPS6461361A (en) * | 1987-09-01 | 1989-03-08 | Sumitomo Electric Industries | Aluminum nitride sintered compact having high heat conductivity |
| JP2664063B2 (en) * | 1988-05-27 | 1997-10-15 | 住友電気工業株式会社 | Aluminum nitride pre-sintered body, aluminum nitride sintered body, and method for producing them |
-
1989
- 1989-04-18 JP JP1098496A patent/JP2742599B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02279567A (en) | 1990-11-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4571728B2 (en) | Silicon nitride sintered body and manufacturing method thereof | |
| JP3214890B2 (en) | Aluminum nitride sintered body, method for producing the same, and firing jig using the same | |
| WO2020059035A1 (en) | Aluminum nitride sintered compact and method for producing same | |
| JP2742600B2 (en) | Aluminum nitride sintered body and method for producing the same | |
| JP2742599B2 (en) | Aluminum nitride sintered body and method for producing the same | |
| JP2899893B2 (en) | Aluminum nitride sintered body and method for producing the same | |
| JP2742598B2 (en) | Aluminum nitride sintered body and method for producing the same | |
| JP3561153B2 (en) | Silicon nitride heat dissipation member and method of manufacturing the same | |
| JP2851716B2 (en) | Aluminum nitride circuit board | |
| JP2807430B2 (en) | Aluminum nitride sintered body and method for producing the same | |
| US5250478A (en) | Aluminum nitride sintered body and process for preparation thereof | |
| JP2535139B2 (en) | Heat dissipation board | |
| JP2630157B2 (en) | Manufacturing method of aluminum nitride sintered body | |
| JPH0238366A (en) | Sintered material of aluminum nitride and production thereof | |
| JP2772580B2 (en) | Method for producing aluminum nitride sintered body | |
| JP2851712B2 (en) | Aluminum nitride circuit board | |
| JP2704194B2 (en) | Black aluminum nitride sintered body | |
| JP2720094B2 (en) | Method for manufacturing aluminum nitride substrate | |
| JP3347526B2 (en) | Aluminum nitride sintered body and method for producing the same | |
| JPS61146766A (en) | Aluminum nitride sintered body and manufacture | |
| JP2698014B2 (en) | Manufacturing method of aluminum nitride sintered body | |
| JP2772581B2 (en) | Black aluminum nitride sintered body | |
| JPH0881266A (en) | Production of aluminum nitride sintered compact | |
| JP2892195B2 (en) | Manufacturing method of AlN firing jig | |
| KR20210062783A (en) | Aluminium nitride ceramics and manufacturing method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |