JPS63230574A - Manufacture of aluminum nitride sintered body - Google Patents
Manufacture of aluminum nitride sintered bodyInfo
- Publication number
- JPS63230574A JPS63230574A JP62062665A JP6266587A JPS63230574A JP S63230574 A JPS63230574 A JP S63230574A JP 62062665 A JP62062665 A JP 62062665A JP 6266587 A JP6266587 A JP 6266587A JP S63230574 A JPS63230574 A JP S63230574A
- Authority
- JP
- Japan
- Prior art keywords
- aluminum nitride
- sintered body
- nitride sintered
- sintering
- thermal conductivity
- 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
Links
- PMHQVHHXPFUNSP-UHFFFAOYSA-M copper(1+);methylsulfanylmethane;bromide Chemical compound Br[Cu].CSC PMHQVHHXPFUNSP-UHFFFAOYSA-M 0.000 title claims description 27
- 238000004519 manufacturing process Methods 0.000 title claims description 8
- 238000005245 sintering Methods 0.000 claims description 16
- 239000000843 powder Substances 0.000 claims description 13
- XHCLAFWTIXFWPH-UHFFFAOYSA-N [O-2].[O-2].[O-2].[O-2].[O-2].[V+5].[V+5] Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[V+5].[V+5] XHCLAFWTIXFWPH-UHFFFAOYSA-N 0.000 claims description 10
- 229910001935 vanadium oxide Inorganic materials 0.000 claims description 10
- 239000000654 additive Substances 0.000 claims 1
- 230000000996 additive effect Effects 0.000 claims 1
- 239000000203 mixture Substances 0.000 claims 1
- 239000000463 material Substances 0.000 description 11
- 238000000034 method Methods 0.000 description 10
- 239000000758 substrate Substances 0.000 description 6
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 5
- 239000007789 gas Substances 0.000 description 5
- 239000002245 particle Substances 0.000 description 5
- 229910052710 silicon Inorganic materials 0.000 description 5
- 239000010703 silicon Substances 0.000 description 5
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 4
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 4
- 238000005452 bending Methods 0.000 description 4
- 230000017525 heat dissipation Effects 0.000 description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 3
- 229910001873 dinitrogen Inorganic materials 0.000 description 3
- 229910052786 argon Inorganic materials 0.000 description 2
- QVQLCTNNEUAWMS-UHFFFAOYSA-N barium oxide Chemical compound [Ba]=O QVQLCTNNEUAWMS-UHFFFAOYSA-N 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000010304 firing Methods 0.000 description 2
- 239000001307 helium Substances 0.000 description 2
- 229910052734 helium Inorganic materials 0.000 description 2
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 description 1
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 1
- 239000000292 calcium oxide Substances 0.000 description 1
- 229910002090 carbon oxide Inorganic materials 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000010292 electrical insulation Methods 0.000 description 1
- 238000001513 hot isostatic pressing Methods 0.000 description 1
- 238000007731 hot pressing Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- UFQXGXDIJMBKTC-UHFFFAOYSA-N oxostrontium Chemical compound [Sr]=O UFQXGXDIJMBKTC-UHFFFAOYSA-N 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000001272 pressureless sintering Methods 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000007740 vapor deposition Methods 0.000 description 1
Landscapes
- Ceramic Products (AREA)
Abstract
(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.
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.
［従来の技術］
近年、半導体工業の急速な技術革新により、ＩＣ，ＬＳ
Ｉをはじめとする大規模集積回路は高集積化、高出力化
が行われ、これに伴うシリコン素子の単位面積当りの発
熱量が大幅に増加してきた。そこでシリコン素子の通電
動作による発熱のためシリコン素子の正常な動作を防げ
る問題が生じ始めている。それに伴って熱伝導性の良い
絶縁性基板材料が要求されている。[Conventional technology] In recent years, due to rapid technological innovation in the semiconductor industry, IC, LS
Large-scale integrated circuits such as I have become highly integrated and have high output, and the amount of heat generated per unit area of silicon elements has accordingly increased significantly. Therefore, a problem has begun to arise in which the normal operation of the silicon element is prevented due to the heat generated by the energizing operation of the silicon element. Accordingly, insulating substrate materials with good thermal conductivity are required.
従来、絶縁性基板材料としては一般にアルミナ焼結体が
最も多く使用されている。しかしながら、最近ではアル
ミナ基板は熱放散に関しては満足しているとは言えず、
さらに熱放散性（熱伝導性）の優れた絶縁性基板材料の
開発が要求されるようになってきた。このような絶縁基
板材料としては熱伝導性が良い（熱伝導率が大きい）、
電気絶縁性である。熱膨張率がシリコン単結晶の値に近
い、機械的強度が大きい等の特性が要求される。Conventionally, alumina sintered bodies have been most commonly used as insulating substrate materials. However, recently, alumina substrates cannot be said to be satisfactory in terms of heat dissipation.
Furthermore, there has been a demand for the development of insulating substrate materials with excellent heat dissipation (thermal conductivity). As such an insulating substrate material, it has good thermal conductivity (high thermal conductivity).
It is electrically insulating. It is required to have properties such as a coefficient of thermal expansion close to that of a silicon single crystal and high mechanical strength.
ところで、良好な熱伝導性を有することが知られている
窒化アルミニウムは熱膨張率が約４．３Ｘ ＩＦ６／’
０ （室温カラ４００℃平均値）テアルミナ焼結体の約
７Ｘ １０−６／ｌに比べて小さく、シリコン素子の熱
膨張率３．５〜４．ＯＸＩＦ６７℃に近い、また機械的
強度も曲げ強さで約５゜Ｋｇ／１１２程度を有し、アル
ミナ焼結体の値２０〜３０Ｋｇ／ ｍｍ２に比べ高強度
であり電気絶縁性に優れた材料である。By the way, aluminum nitride, which is known to have good thermal conductivity, has a coefficient of thermal expansion of approximately 4.3X IF6/'
0 (average value from room temperature to 400°C) It is smaller than the approximately 7X 10-6/l of the alumina sintered body, and the thermal expansion coefficient of the silicon element is 3.5 to 4. It is close to OXIF 67℃, and has a mechanical strength of about 5゜Kg/112 in terms of bending strength, which is higher than the 20-30Kg/mm2 of alumina sintered body, and is a material with excellent electrical insulation properties. be.
従来、窒化アルミニウム（ＡＩＭ）焼結体は窒化アルミ
ニウムの粉末を成形、焼成して得られるのであるが、窒
化アルミニウムは難焼結性物質であるため緻密な焼結体
を得ることが困難である。そして現在までに焼結助剤を
加え、常圧焼結法やホットプレス法により緻密な窒化ア
ルミニウム焼結体を得る試みがなされている。特開昭５
４−１００４１０には酸化カルシウム（Ｃａｂ）、酸化
バリウム（Ｂａｄ）、 醸化ストロンチウム（ＳｒＯ）
等を焼結助剤として加える窒化アルミニウム焼結体の製
造方法が示されている。この方法によると、一般に、熱
伝導率が５０〜８０Ｗ ／ｍｋ （室温）の窒化アルミ
ニウム焼結体が得られている。しかしながら近年の集積
回路技術の発達に伴い、さらに高熱伝導性を有する熱放
散用基板材料が求められている。かかる材料としてＹ２
Ｏ３を焼結助剤とするものが知られているがこの材料は
曲げ強度が低いという問題点があった。Conventionally, aluminum nitride (AIM) sintered bodies are obtained by molding and firing aluminum nitride powder, but since aluminum nitride is a difficult-to-sinter substance, it is difficult to obtain dense sintered bodies. . Up to now, attempts have been made to obtain a dense aluminum nitride sintered body by adding a sintering aid and using pressureless sintering or hot pressing. Japanese Patent Application Publication No. 5
4-100410 contains calcium oxide (Cab), barium oxide (Bad), and strontium oxide (SrO).
A method for manufacturing an aluminum nitride sintered body is shown in which sintered aluminum nitride is added as a sintering aid. According to this method, an aluminum nitride sintered body having a thermal conductivity of 50 to 80 W/mk (room temperature) is generally obtained. However, with the recent development of integrated circuit technology, there is a demand for heat dissipation substrate materials having even higher thermal conductivity. Y2 as such material
A material using O3 as a sintering aid is known, but this material has a problem of low bending strength.
［発明の解決しようとする問題点］
本発明の目的は熱伝導率が大きく、かつ曲げ強度の大き
い窒化アルミニウム焼結体の製造法の提供を目的とする
。[Problems to be Solved by the Invention] An object of the present invention is to provide a method for producing an aluminum nitride sintered body having high thermal conductivity and high bending strength.
［問題点を解決するための手段］
即ち、本発明は窒化アルミニウムの粉末に、酸化バナジ
ウムの粉末を添加して焼結することを特徴とする窒化ア
ルミニウム焼結体の製造法を提供するものである。[Means for Solving the Problems] That is, the present invention provides a method for producing an aluminum nitride sintered body, which is characterized in that vanadium oxide powder is added to aluminum nitride powder and sintered. be.
以下、本発明について具体的に説明する。The present invention will be explained in detail below.
まず、窒化アルミニウムの粉末は高純度のもの、例えば
９８％以上のものが好ましいが８５〜９８％程度のもの
も使用可能である０粒径は１０ｇｍ以下、好ましくは１
ＪＬ１１以下のものが良い。First, the aluminum nitride powder has a high purity, preferably 98% or higher, but 85-98% can also be used.The particle size is 10gm or less, preferably 1
JL11 or lower is best.
粒径が大きくなり過ぎると気泡が残存し易くなるので好
ましくない、一方、粒径が小さくなり過ぎると酸化され
易くなるので好ましくない０粒径は上記範囲中０．２〜
ｌ ｇｒａの範囲が好ましい、かかる窒化アルミニウム
の粉末に添加される酸化バナジウムは、焼結助剤として
作用し緻密な焼結体を得るもので、Ｖ 、 Ｖ２０ａ、
Ｙ２Ｏ３、Ｙ２Ｏ５、の粉末が使用される。酸化バナジ
ウムの添加量は少な過ぎると緻密な焼結体が得られ難く
なり熱伝導率が小さくなるので好ましくない、一方酸化
バナジウムの添加量が多くなり過ぎると相対的に窒化ア
ルミニウムの含有量が少なくなると共に緻密な焼結体が
得られ難くなり熱伝導率が低下するので好ましくない、
好ましい酸化バナジウムの添加量は無機成分中の酸化バ
ナジウムの含有量が０．Ｏ１〜１０．０重量％になる範
囲であり、特に好ましい範囲は０．０１〜５．０重量％
である。また、酸化バナジウムの粒径は０．０１〜１０
ル層の範囲のものが好ましく、この範囲より小さいもの
は１０ＩＬ■以上大きな固溶体が生成し不均質になり強
度が低下し易いので好ましくなく、細か過ぎると分散性
が低下し不均質になり易いので好ましくない。If the particle size becomes too large, air bubbles tend to remain, which is undesirable.On the other hand, if the particle size becomes too small, it becomes easy to oxidize, which is not preferable.
The vanadium oxide added to the aluminum nitride powder, preferably in the range of l gra, acts as a sintering aid to obtain a dense sintered body, and the vanadium oxide is preferably in the range of V , V20a,
Powders of Y2O3 and Y2O5 are used. If the amount of vanadium oxide added is too small, it will be difficult to obtain a dense sintered body and the thermal conductivity will be low, which is undesirable.On the other hand, if the amount of vanadium oxide added is too large, the content of aluminum nitride will be relatively low. This is not preferable because it becomes difficult to obtain a dense sintered body and the thermal conductivity decreases.
The preferred amount of vanadium oxide added is such that the content of vanadium oxide in the inorganic component is 0. O is in the range of 1 to 10.0% by weight, and a particularly preferable range is 0.01 to 5.0% by weight.
It is. In addition, the particle size of vanadium oxide is 0.01 to 10
It is preferable that the layer is in the range of 100 μl, and if it is smaller than this range, a solid solution larger than 10 IL will be generated, resulting in non-uniformity and a decrease in strength, so it is not preferable. Undesirable.
焼結に当っては、窒化アルミニウムの粉末と酸化バナジ
ウムの粉末を所定の割合で混合し、これをプレス等の常
法手段により所定形状に予ｉ成形を行ない、それを常圧
下で焼成することにより焼結体を得ることができる。
焼結は加圧焼結法によっても良い、加圧焼結法としては
ホットプレス法（−軸加工焼結法）とＨＩＰ法（熱間静
水圧加圧焼結法）のどちらでも可能である。その際の圧
力としては１０００〜１００００ Ｋｇ／ＣｌＩ２が使
用される。For sintering, aluminum nitride powder and vanadium oxide powder are mixed in a predetermined ratio, pre-formed into a predetermined shape using conventional means such as pressing, and then fired under normal pressure. A sintered body can be obtained.
The sintering may be performed by a pressure sintering method, and the pressure sintering method can be either a hot press method (-shaft processing sintering method) or a HIP method (hot isostatic pressing sintering method). . The pressure used at this time is 1000 to 10000 Kg/ClI2.
焼結は非酸化性雰囲気中で焼結することが好ましく、こ
れより酸素濃度の高い雰囲気で焼成すると窒化アルミニ
ウムが酸化し緻密な焼結体が得られ難いので好ましくな
い、非酸化性雰囲気としては窒素ガス、ヘリウムガス、
アルゴンガス、−酸化炭素ガス、水素ガス、真空雰囲気
などが使用できるが、中でも窒素ガス、アルゴンガス、
ヘリウムガス、真空雰囲気が便利で好ましい、焼結の温
度としては１５００〜２０００’Ｏの範囲、特に１７０
０〜２０００’０の範囲が有効である。また焼結の時間
としては上記温度に２〜５時間保持することで充分に目
的とする焼結体を得ることができる。It is preferable to sinter in a non-oxidizing atmosphere. Sintering in an atmosphere with a higher oxygen concentration than this is not preferable because aluminum nitride will oxidize and it will be difficult to obtain a dense sintered body. nitrogen gas, helium gas,
Argon gas, carbon oxide gas, hydrogen gas, vacuum atmosphere, etc. can be used, but among them nitrogen gas, argon gas,
Helium gas or vacuum atmosphere is convenient and preferable, and the sintering temperature is in the range of 1500 to 2000'O, especially 170
A range of 0 to 2000'0 is valid. The desired sintered body can be sufficiently obtained by maintaining the sintering temperature at the above temperature for 2 to 5 hours.
なお、焼結温度は加圧焼結法を採用することにより低温
度にすることができる。Note that the sintering temperature can be lowered by employing a pressure sintering method.
［実施例］
平均粒度が２４ｍの窒化アルミニウム粉末にＹ２Ｏ３粉
末を添加混合した０次いでこの粉末を室温で４００Ｋｇ
／ ｃｍ２の圧力を加えて成形体とした。この成形体を
窒化アルミニウムるつぼ内におき焼成炉において窒素ガ
ス雰囲気下１８５０℃で５時間保持して窒化アルミニウ
ム焼結体を得た。この窒化アルミニウム焼結体にづいて
測定した相対密度、熱伝導率、電気抵抗率、抵抗強度を
測定した。これらの測定結果及びＹ２Ｏ３の添加量を第
１表に示した。比較例としてＣａＯ０３、Ｙ２Ｏ３を使
用した場合のものについても同様の測定を行いその結果
も同表に併記した。[Example] Y2O3 powder was added and mixed to aluminum nitride powder with an average particle size of 24 m.Then, this powder was mixed at 400 kg at room temperature.
A pressure of /cm2 was applied to form a molded body. This molded body was placed in an aluminum nitride crucible and held at 1850° C. for 5 hours in a nitrogen gas atmosphere in a firing furnace to obtain an aluminum nitride sintered body. The relative density, thermal conductivity, electrical resistivity, and resistance strength of this aluminum nitride sintered body were measured. These measurement results and the amount of Y2O3 added are shown in Table 1. As a comparative example, similar measurements were carried out using CaO03 and Y2O3, and the results are also listed in the same table.
同表より明らかなように本発明により得られる焼結体は
Ｙ２Ｏ３を用いたものに比べ熱伝導率は同程度であるも
のの折抗強度が優れ、電気抵抗率も優れる。As is clear from the table, the sintered body obtained according to the present invention has comparable thermal conductivity to those using Y2O3, but has superior bending strength and electrical resistivity.
［発明の効果］
本発明の製造方法で製造した窒化アルミニウム焼結体は
高密度で熱伝導性に優れ、熱的特性、電気的特性、機械
的特性に良好であったため、半導体工業等の放熱材料と
して応用以外にルツボ、蒸着用容器、耐熱ジグ高温部材
等の高温材料としての応用も可能であり、工業的に多く
の利点を有するものである。[Effects of the Invention] The aluminum nitride sintered body produced by the production method of the present invention has high density, excellent thermal conductivity, and good thermal, electrical, and mechanical properties, so it is suitable for heat dissipation in the semiconductor industry, etc. In addition to being used as a material, it can also be used as a high-temperature material for crucibles, vapor deposition containers, heat-resistant jigs, and other high-temperature members, and has many industrial advantages.
Claims (2)
末を添加して焼結することを特徴とする窒化アルミニウ
ム焼結体の製造法。(1) A method for producing an aluminum nitride sintered body, which comprises adding vanadium oxide powder to aluminum nitride powder and sintering the mixture.
れてなる特許請求の範囲第１項の窒化アルミニウム焼結
体の製造法。(2) The method for producing an aluminum nitride sintered body according to claim 1, wherein the additive is blended in a total amount of 0.01 to 10% by weight.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62062665A JPH0832593B2 (en) | 1987-03-19 | 1987-03-19 | Manufacturing method of aluminum nitride sintered body |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62062665A JPH0832593B2 (en) | 1987-03-19 | 1987-03-19 | Manufacturing method of aluminum nitride sintered body |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63230574A true JPS63230574A (en) | 1988-09-27 |
| JPH0832593B2 JPH0832593B2 (en) | 1996-03-29 |
Family
ID=13206815
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62062665A Expired - Lifetime JPH0832593B2 (en) | 1987-03-19 | 1987-03-19 | Manufacturing method of aluminum nitride sintered body |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0832593B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000327425A (en) * | 1999-03-17 | 2000-11-28 | Asahi Techno Glass Corp | Aluminum nitride sintered compact and its production |
-
1987
- 1987-03-19 JP JP62062665A patent/JPH0832593B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000327425A (en) * | 1999-03-17 | 2000-11-28 | Asahi Techno Glass Corp | Aluminum nitride sintered compact and its production |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0832593B2 (en) | 1996-03-29 |
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