JP3559313B2 - Colored alumina sintered body - Google Patents

Colored alumina sintered body Download PDF

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JP3559313B2
JP3559313B2 JP14949094A JP14949094A JP3559313B2 JP 3559313 B2 JP3559313 B2 JP 3559313B2 JP 14949094 A JP14949094 A JP 14949094A JP 14949094 A JP14949094 A JP 14949094A JP 3559313 B2 JP3559313 B2 JP 3559313B2
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sintered body
oxide
weight
terms
alumina
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JPH0812416A (en
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照夫 近藤
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Kyocera Corp
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Kyocera Corp
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Description

【0001】
【産業上の利用分野】
本発明は、例えば、半導体搭載用パッケージ等の絶縁基板などに適した着色アルミナ質焼結体に関するものである。
【0002】
【従来技術】
従来、セラミックス素材に要求される特性としては、耐熱性等の熱的性質、強度等の機械的性質、耐食性等の化学的性質、導電性等の電磁気的性質がある。近年、電子部品,半導体製造用部品、各種測定装置等においては、黒色セラミックスが要求されてきている。これはわずかな塵埃がこれらの部品の精度や性能に大きく影響するが、黒色の場合にはこれらの塵埃の存在をいち早く見出すことができるためである。また、黒色の場合には部品が摩耗したり、破損した場合、その部位をはっきりと識別することができるからである。さらに、黒色は重厚感があり、審美性に優れるからである。
【0003】
このような黒色セラミックスのうち、黒色アルミナ質焼結体は、従来、Alを主成分とし、SiO,TiO,CuO,NiO,Fe等の顔料を添加し、成形後1300℃以上の温度で焼成することにより製造されていた。
【0004】
このようなアルミナ質焼結体は重厚感あふれる黒色を有しており、審美性に優れている。
【0005】
【発明が解決しようとする問題点】
しかしながら、このような黒色アルミナ質焼結体は、良好な着色性を得るためには、原料全量に対して多量の顔料を添加する必要があった。そのため、得られる焼結体の物性は大きく低下するという問題があった。
【0006】
即ち、多量の顔料の添加は、高温物性の低下、電気絶縁性の著しい低下等を引き起こすため、アルミナ質焼結体特有の電気的、機械的、熱的特性を損なってしまうという欠点があった。
【0007】
また、例えば、半導体搭載用パッケージに用いられる絶縁基板等のセラミック製品を製造する工程では、搬送中に焼結体が相互に衝突したり、他の部材と衝突したりすることがあるが、この場合には、焼結体の角が欠け易く、製品不良が多くなるという問題があった。
【0008】
従って、本発明の着色アルミナ質焼結体は、比較的多量の顔料を添加した場合でも、優れた特性を有するとともに、焼結体の破損を抑制することができる着色アルミナ質焼結体を得ることを目的とする。
【0009】
【問題点を解決するための手段】
本発明者は、上記のような問題点について鋭意検討した結果、Tiの酸化物と、周期律表第5A族元素の酸化物と、Cr,Co,Si,Mnの酸化物を所定量含有するとともに、残部がAlからなる焼結体は、審美性に優れた暗色系の色彩を呈しながらも、優れた電気的、機械的および熱的特性を有するとともに、焼結体の破損を抑制することができることを見出し本発明に至った。
【0010】
即ち、本発明の着色アルミナ質焼結体は、Tiが酸化物換算で1〜3重量%と、Vが酸化物換算で0.2〜0.35重量%と、Crが酸化物換算で2〜3重量%と、Coが酸化物換算で0.2〜0.3重量%と、Siが酸化物換算で0.2〜2.0重量%と、Mnが酸化物換算で2〜5重量%と、残部がAl からなり、抗折強度が30kg/mm 以上、硬度が1290kg/mm 以上の機械特性を有するとともに、25℃において1×10 11 Ωcm以上の絶縁抵抗を有するものである
【0011】
以下、本発明を詳述する。
本発明のアルミナ質焼結体において、Alに対する各添加成分量を上記の範囲に限定した理由について説明すると、まず、Tiは酸化物換算で1〜5重量%、特に1.0〜2.5重量%の割合で含有される。これは、Tiの含有量が酸化物換算で1重量%よりも少ない場合には、黒色に対する着色効果が少なくなり、焼結温度が高くなる傾向にあり、さらに欠け易くなるからである。また、5重量%よりも多いと絶縁抵抗が低下し、絶縁基板としての用途に適しないためである。
【0012】
さらに、周期律表第5A族元素は、酸化物換算で0.2〜0.4重量%、特に0.25〜0.35重量%の割合で含有されるが、周期律表第5A族元素量が0.2重量%よりも少ないと、焼結しにくくなり、強度が低下するからである。また、0.4重量%よりも多いと絶縁抵抗が低下するからである。この周期律表第5A族元素は、焼結体に良好な黒色を付与するとともに、絶縁抵抗を安定させる特性を有しており、このような周期律表第5A族元素としては、Ta、Nb、Vが挙げられる。
【0013】
また、Cr,Co,SiおよびMnの群から選ばれる少なくとも1種を酸化物換算で5〜15重量%、特に5〜8重量%の割合で含有されるが、これらの添加により色彩を調整したり、焼成温度を制御するためのものであり、これらの添加量が5重量%よりも少ない場合には焼成温度が高くなるとともに、色彩が薄くなり、重厚感溢れる色彩が得られないからであり、15重量%よりも多い場合には絶縁抵抗が低下し、欠け易くなるからである。なお、焼成温度を低温化するためには、これらの元素のうち2種以上を含有することが望ましい。その場合、Cr、SiOおよびMnOは合計で5.0〜10.0重量%の割合で含有することが望ましい。
【0014】
本発明の着色アルミナ質焼結体における最も望ましい範囲は、Tiが酸化物換算で1〜3重量%と、Vが酸化物換算で0.2〜0.35重量%と、Crが酸化物換算で2〜3重量%と、Coが酸化物換算で0.2〜0.3重量%と、Siが酸化物換算で0.2〜2.0重量%と、Mnが酸化物換算で2〜5重量%と、残部がAlからなることが望ましい。
【0015】
本発明における着色アルミナ質焼結体は、例えば、Al粉末、TiO粉末、周期律表第5A族元素酸化物粉末、Cr粉末、CoO粉末、SiO粉末、MnO粉末や、熱処理により前記のような酸化物となり得る、例えば炭酸塩、硝酸塩、酢酸塩、水酸化物などを用いて、前述したような組成となるように十分に混合する。その際、ミルのボールからの他の成分の混入がある場合、各成分の組成が前述した範囲を逸脱しないように考慮することが必要である。次に、この混合物をプレス成形や押し出し成形、ドクターブレード法などの周知の成形手段により成形した後、大気などの酸化性雰囲気中で1350〜1650℃の温度で0.5〜5時間程度焼成することにより相対密度比が98%以上の緻密質な焼結体を得ることができる。
【0016】
【作用】
本発明の着色アルミナ質焼結体では、重量感溢れる暗色系の色彩を呈するとともに、Cr,Co,Si,Mnなどの顔料成分を比較的多量に添加した場合でも、従来のAl焼結体の絶縁性に近い高い絶縁性を有し、Alとほぼ同等の強度を有するとともに、半導体パッケージ用の絶縁基体として用いた場合において、基板の搬送過程での基板の角の欠けなどがなく安定した製造が可能となる。
【0017】
以下、本発明を次の例で説明する。
【0018】
【実施例】
原料粉末として、平均粒径が1μmのAl粉末に対して、添加成分としてTiONb、Ta、V、Cr、CoO、SiOおよびMnOの各粉末を表1に示すような割合となるように秤量後、ボールミルで混合した。これを乾燥造粒後、1000kg/cmの圧力でプレス成形した後、表1に示す条件で焼成した。
【0019】
【表1】

Figure 0003559313
【0020】
得られた焼結体に対して色調を調べるとともに、焼結体より抗折試験片を切り出しJISR1601による3点曲げ抗折強度、荷重500gでのビッカース硬度Hv、及びアルキメデス法により相対密度を算出した。また、JISC2141に基づき絶縁抵抗を測定した。さらに、欠け易さを調べる試験を行った。この欠け易さの試験は、各試料よりテスト基板(縦25mm、横25mm、厚み1mm、エッジ部は0.1〜0.2R処理)を作製し、図1に示すような試験機を用いて行った。この試験機は、鉄板1と樹脂よりなる30°の傾斜を有する斜面2とから構成されている。そして、斜面2からテスト基板3を滑らせ、その4つの辺をそれぞれ鉄板1に衝突させ、1mm以上の欠けが生じた基板をカウントした。欠け易さの試験は、各々の試料について100枚ずつ行った。
【0021】
また、各試料を直径20mm厚み10mmの円柱体形状に加工し、両端面を銅板で短絡し、誘電体円柱共振法により、TE011 モードの共振特性条件で比誘電率及び誘電正接を測定した。この結果を表2に示す。
【0022】
【表2】
Figure 0003559313
【0023】
この表2より、本発明における組成範囲を逸脱する試料No.1,6,7,11,12,17,19では、色調、強度、硬度、絶縁抵抗、欠け性などの点で満足すべきものは得られなかった。特に従来のアルミナ磁器である試料No.19では色調がアイボリーであり、色調の点で満足するものではなかった。一方、本発明の組成範囲を満足する試料は、いずれも良好な暗色系の色彩を呈し、かつ強度,硬度,電気絶縁性等の物性も良好であり、30kg/mm以上の抗折強度、1290kg/mm以上の硬度を有し、アルミナ単独並みの機械的特性を有するとともに、25℃において1×1011Ωcm以上の絶縁抵抗を有するものであった。
【0024】
尚、試料No.18について、80℃における絶縁抵抗を測定したところ1×1011Ωcmであった。また、本発明の着色アルミナ質焼結体は、欠け難さの点で従来のアルミナ質焼結体よりも大幅に向上していることが判る。
【0025】
【発明の効果】
以上詳述した通り、本発明の着色アルミナ質焼結体は、重厚感溢れる暗色系の色彩を有するとともに、高い強度,硬度,電気絶縁性等の物性を有するとともに欠け難いものであり、半導体パッケージなどの製造工程においても破損が少ないため不良率を少なくすることができる。
【図面の簡単な説明】
【図1】欠け易さ試験機を示す側面図である。
【符号の説明】
1・・・鉄板
2・・・斜面
3・・・基板[0001]
[Industrial applications]
The present invention relates to a colored alumina sintered body suitable for, for example, an insulating substrate such as a semiconductor mounting package.
[0002]
[Prior art]
Conventionally, properties required for ceramic materials include thermal properties such as heat resistance, mechanical properties such as strength, chemical properties such as corrosion resistance, and electromagnetic properties such as conductivity. 2. Description of the Related Art In recent years, black ceramics have been required for electronic components, semiconductor manufacturing components, various measuring devices, and the like. This is because a small amount of dust greatly affects the accuracy and performance of these components, but the presence of these dusts can be quickly detected in the case of black. Also, if the part is worn or damaged in the case of black, the part can be clearly identified. Further, black has a profound feeling and is excellent in aesthetics.
[0003]
Among such black ceramics, conventionally, a black alumina-based sintered body has Al 2 O 3 as a main component, and a pigment such as SiO 2 , TiO 2 , CuO, NiO, Fe 2 O 3 is added, and after molding, It was manufactured by firing at a temperature of 1300 ° C. or higher.
[0004]
Such an alumina-based sintered body has a solid black color and is excellent in aesthetics.
[0005]
[Problems to be solved by the invention]
However, in such a black alumina sintered body, it was necessary to add a large amount of pigment to the entire raw material in order to obtain good coloring properties. Therefore, there is a problem that the physical properties of the obtained sintered body are greatly reduced.
[0006]
That is, the addition of a large amount of pigment causes a decrease in high-temperature physical properties, a significant decrease in electrical insulation, and the like, so that the electrical, mechanical, and thermal characteristics peculiar to the alumina-based sintered body are impaired. .
[0007]
Further, for example, in a process of manufacturing a ceramic product such as an insulating substrate used for a semiconductor mounting package, the sintered bodies may collide with each other during transportation or may collide with other members. In such a case, there is a problem that corners of the sintered body are easily chipped and the number of defective products increases.
[0008]
Therefore, the colored alumina-based sintered body of the present invention has excellent characteristics even when a relatively large amount of pigment is added, and obtains a colored alumina-based sintered body capable of suppressing damage to the sintered body. The purpose is to:
[0009]
[Means for solving the problem]
As a result of intensive studies on the above problems, the present inventor has found that a predetermined amount of an oxide of Ti, an oxide of a Group 5A element of the periodic table, and an oxide of Cr, Co, Si, and Mn are contained. At the same time, the sintered body composed of Al 2 O 3 with the balance has excellent electrical, mechanical and thermal properties while exhibiting a dark color excellent in aesthetics, and also has a high possibility of damage to the sintered body. The present inventors have found that it can be suppressed, and have reached the present invention.
[0010]
That is, in the colored alumina sintered body of the present invention, Ti is 1 to 3% by weight in terms of oxide, V is 0.2 to 0.35% by weight in terms of oxide, and Cr is 2% in terms of oxide. -3 wt%, Co is 0.2-0.3 wt% in terms of oxide, Si is 0.2-2.0 wt% in terms of oxide, and Mn is 2-5 wt% in terms of oxide. a percent, and the balance of Al 2 O 3, flexural strength 30kg / mm 2 or more, with hardness has a 1290kg / mm 2 or more mechanical properties, a 1 × 10 11 Ωcm or more insulation resistance at 25 ° C. Things .
[0011]
Hereinafter, the present invention will be described in detail.
In the alumina sintered body of the present invention, the reason why the amount of each additive component relative to Al 2 O 3 is limited to the above range will be described. First, Ti is 1 to 5% by weight in terms of oxide, particularly 1.0 to 1.0% by weight. It is contained in a proportion of 2.5% by weight. This is because, when the content of Ti is less than 1% by weight in terms of oxide, the coloring effect on black decreases, the sintering temperature tends to increase, and chipping is more likely. On the other hand, if the content is more than 5% by weight, the insulation resistance is reduced, which is not suitable for use as an insulating substrate.
[0012]
Further, the group 5A element of the periodic table is contained at a ratio of 0.2 to 0.4% by weight, particularly 0.25 to 0.35% by weight in terms of oxide, but the group 5A element of the periodic table is contained. If the amount is less than 0.2% by weight, sintering becomes difficult and the strength decreases. Also, if it is more than 0.4% by weight, the insulation resistance is reduced. The group 5A element of the periodic table has characteristics of imparting a good black color to the sintered body and stabilizing the insulation resistance. Such group 5A elements of the periodic table include Ta, Nb , V.
[0013]
Further, at least one selected from the group consisting of Cr, Co, Si and Mn is contained in a proportion of 5 to 15% by weight, especially 5 to 8% by weight in terms of oxide, and the color is adjusted by adding these. Or to control the firing temperature, and when the amount of addition of these is less than 5% by weight, the firing temperature increases and the color becomes lighter, and a color full of profound feeling cannot be obtained. If the content is more than 15% by weight, insulation resistance is reduced and chipping is likely to occur. In order to lower the firing temperature, it is desirable to contain two or more of these elements. In that case, it is desirable that Cr 2 O 3 , SiO 2 and MnO 2 be contained in a total amount of 5.0 to 10.0% by weight.
[0014]
The most desirable ranges of the colored alumina sintered body of the present invention are as follows: Ti is 1 to 3% by weight in terms of oxide; V is 0.2 to 0.35% by weight in terms of oxide; 2 to 3% by weight, Co is 0.2 to 0.3% by weight in terms of oxide, Si is 0.2 to 2.0% by weight in terms of oxide, and Mn is 2 to 2% in terms of oxide. It is desirable that 5% by weight and the balance be made of Al 2 O 3 .
[0015]
The colored alumina-based sintered body in the present invention is, for example, Al 2 O 3 powder, TiO 2 powder, Group 5A element oxide powder, Cr 2 O 3 powder, CoO powder, SiO 2 powder, MnO 2 powder. Alternatively, using a carbonate, a nitrate, an acetate, a hydroxide, or the like, which can become the above-described oxide by heat treatment, the mixture is sufficiently mixed so as to have the above-described composition. At this time, when other components are mixed from the ball of the mill, it is necessary to consider that the composition of each component does not deviate from the above-mentioned range. Next, this mixture is molded by a known molding means such as press molding, extrusion molding, or a doctor blade method, and then fired at a temperature of 1350 to 1650 ° C. for 0.5 to 5 hours in an oxidizing atmosphere such as air. As a result, a dense sintered body having a relative density ratio of 98% or more can be obtained.
[0016]
[Action]
The colored alumina-based sintered body of the present invention exhibits a dark-colored color overflowing with a heavy feeling, and even when a pigment component such as Cr, Co, Si, or Mn is added in a relatively large amount, the conventional Al 2 O 3 sintered body is used. It has a high insulating property close to the insulating property of the solid body, has almost the same strength as Al 2 O 3, and, when used as an insulating base for a semiconductor package, lacks corners of the board in the course of transferring the board. There is no need for stable production.
[0017]
Hereinafter, the present invention will be described with reference to the following examples.
[0018]
【Example】
As raw material powder, TiO 2 Nb 2 O 5 , Ta 2 O 5 , V 2 O 5 , Cr 2 O 3 , CoO, SiO 2 and MnO are added to Al 2 O 3 powder having an average particle diameter of 1 μm as additive components. Each powder of No. 2 was weighed so as to have a ratio as shown in Table 1, and then mixed by a ball mill. This was dried, granulated, press-molded at a pressure of 1000 kg / cm 2 , and fired under the conditions shown in Table 1.
[0019]
[Table 1]
Figure 0003559313
[0020]
The color tone of the obtained sintered body was examined, a bending test piece was cut out from the sintered body, and a three-point bending bending strength according to JISR1601, a Vickers hardness Hv at a load of 500 g, and a relative density were calculated by an Archimedes method. . The insulation resistance was measured based on JISC2141. Further, a test for examining the easiness of chipping was performed. In the test of the easiness of chipping, a test substrate (length 25 mm, width 25 mm, thickness 1 mm, edge portion is treated with 0.1 to 0.2 R) is prepared from each sample, and a test machine as shown in FIG. 1 is used. went. This tester includes an iron plate 1 and a slope 2 made of resin and having a slope of 30 °. Then, the test board 3 was slid from the slope 2 and the four sides of the test board 3 collided with the iron plate 1, respectively. The test for chipping easiness was performed on 100 samples of each sample.
[0021]
Each sample was processed into a cylindrical shape having a diameter of 20 mm and a thickness of 10 mm, both ends were short-circuited with a copper plate, and the relative permittivity and the dielectric loss tangent were measured by a dielectric cylinder resonance method under the TE011 mode resonance characteristic condition. Table 2 shows the results.
[0022]
[Table 2]
Figure 0003559313
[0023]
From Table 2, it can be seen that Sample No. deviating from the composition range in the present invention. 1,6,7,11,12,17,19 did not provide satisfactory color tone, strength, hardness, insulation resistance, chipping, and the like. In particular, Sample No. 1 which is a conventional alumina porcelain was used. In No. 19, the color tone was ivory, and the color tone was not satisfactory. On the other hand, all of the samples satisfying the composition range of the present invention exhibit a good dark color and good physical properties such as strength, hardness, and electrical insulation, and have a transverse rupture strength of 30 kg / mm 2 or more. It had a hardness of 1290 kg / mm 2 or more, had mechanical properties comparable to alumina alone, and had an insulation resistance of 1 × 10 11 Ωcm or more at 25 ° C.
[0024]
The sample No. As for No. 18, the insulation resistance at 80 ° C. was 1 × 10 11 Ωcm. In addition, it can be seen that the colored alumina-based sintered body of the present invention is significantly improved from the conventional alumina-based sintered body in terms of difficulty in chipping.
[0025]
【The invention's effect】
As described in detail above, the colored alumina-based sintered body of the present invention has a dark color that overflows with a profound feeling, and has physical properties such as high strength, hardness, and electrical insulation, and is hardly missing. Also in the manufacturing process such as the above, the damage rate is small, so that the defective rate can be reduced.
[Brief description of the drawings]
FIG. 1 is a side view showing a chipping tester.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Iron plate 2 ... Slope 3 ... Board

Claims (1)

Tiが酸化物換算で1〜3重量%と、Vが酸化物換算で0.2〜0.35重量%と、Crが酸化物換算で2〜3重量%と、Coが酸化物換算で0.2〜0.3重量%と、Siが酸化物換算で0.2〜2.0重量%と、Mnが酸化物換算で2〜5重量%と、残部がAl からなり、抗折強度が30kg/mm 以上、硬度が1290kg/mm 以上の機械特性を有するとともに、25℃において1×10 11 Ωcm以上の絶縁抵抗を有するものであることを特徴とする着色アルミナ質焼結体。 Ti is 1-3% by weight in terms of oxide, V is 0.2-0.35% by weight in terms of oxide, Cr is 2-3% by weight in terms of oxide, and Co is 0% in terms of oxide. and .2~0.3 wt%, and 0.2 to 2.0% by weight Si oxide converted, and 2-5% by weight Mn oxide basis, the balance being Al 2 O 3, anti A colored alumina-based sintered material having mechanical properties of a bending strength of 30 kg / mm 2 or more and a hardness of 1290 kg / mm 2 or more and having an insulation resistance of 1 × 10 11 Ωcm or more at 25 ° C. body.
JP14949094A 1994-06-30 1994-06-30 Colored alumina sintered body Expired - Fee Related JP3559313B2 (en)

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JP14949094A JP3559313B2 (en) 1994-06-30 1994-06-30 Colored alumina sintered body

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JPH0812416A JPH0812416A (en) 1996-01-16
JP3559313B2 true JP3559313B2 (en) 2004-09-02

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Publication number Priority date Publication date Assignee Title
JP4735586B2 (en) * 2007-03-30 2011-07-27 東レ株式会社 Manufacturing method of ceramic sintered body
JP2011168420A (en) * 2010-02-17 2011-09-01 Kikusui Chemical Industries Co Ltd Alumina sintered compact and substrate holding board formed by alumina sintered compact
JP2010208943A (en) * 2010-05-17 2010-09-24 Kyocera Corp Low thermal expansion ceramic and method for producing the same
JP6659493B2 (en) * 2016-07-29 2020-03-04 京セラ株式会社 Mounting member

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