JP3273468B2 - Barium titanate-based semiconductor porcelain composition - Google Patents
Barium titanate-based semiconductor porcelain compositionInfo
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- JP3273468B2 JP3273468B2 JP29664190A JP29664190A JP3273468B2 JP 3273468 B2 JP3273468 B2 JP 3273468B2 JP 29664190 A JP29664190 A JP 29664190A JP 29664190 A JP29664190 A JP 29664190A JP 3273468 B2 JP3273468 B2 JP 3273468B2
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- barium titanate
- based semiconductor
- porcelain composition
- semiconductor porcelain
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Description
【０００１】[0001]
この発明は、耐電圧特性に優れ、かつ、比抵抗の小さ
い、正の抵抗温度特性を有するチタン酸バリウム系半導
体磁器組成物に関する。The present invention relates to a barium titanate-based semiconductor ceramic composition having excellent withstand voltage characteristics, low specific resistance, and positive temperature characteristics.
【０００２】[0002]
チタン酸バリウム系半導体磁器組成物はチタン酸バリ
ウム（BaTiO3）に半導体化剤としてＹ、La、Ceなどの希
土類元素、Nb、Bi、Sb、Ｗ、Thなどの元素のうち少なく
とも１種を、酸化物などの形で微量含有させた半導体磁
器組成物であり、温度制御用素子、電流制御用素子その
他種々の用途に広く用いられている。The barium titanate-based semiconductor porcelain composition contains barium titanate (BaTiO 3 ) as a semiconducting agent and at least one of rare earth elements such as Y, La, and Ce, and elements such as Nb, Bi, Sb, W, and Th, A semiconductor porcelain composition containing a trace amount of oxide or the like, and is widely used for temperature control elements, current control elements, and various other applications.
【０００３】 チタン酸バリウム系半導体磁器組成物は、一般に常温
における比抵抗が小さく、キュリー点を越えると著しい
正の抵抗温度特性を示すという特徴を有している。この
チタン酸バリウム系半導体磁器組成物にあっては、その
主成分であるチタン酸バリウムの影響により、キュリー
点は通常120℃付近にあるが、その用途によってはキュ
リー点を高温側あるいは低温側に移行させる必要が生じ
る場合がある。[0003] Barium titanate-based semiconductor porcelain compositions are generally characterized by having low specific resistance at room temperature and exhibiting remarkably positive resistance-temperature characteristics above the Curie point. In this barium titanate-based semiconductor porcelain composition, the Curie point is usually around 120 ° C. due to the effect of barium titanate, which is the main component, but depending on the application, the Curie point is shifted to the high or low temperature side. You may need to migrate.
【０００４】 そこで、このキュリー点を高温側に移行させるために
Baの一部をPbで置換したり、あるいはキュリー点を低温
側に移行させるために、Baの一部をSrで置換したり、Ti
の一部をZr、Snなどで置換したりすることが知られてい
る。In order to shift the Curie point to a higher temperature,
Part of Ba is replaced with Pb, or part of Ba is replaced with Sr to shift the Curie point to the lower temperature side,
Is known to be partially replaced with Zr, Sn, or the like.
【０００５】 さらに、キュリー点を越えた後の、温度による抵抗の
変化率（抵抗温度変化率）を増大させるために、チタン
酸バリウム系半導体磁器組成物にMnを所定の割合で添加
することが知られている。Further, in order to increase the rate of change in resistance due to temperature after exceeding the Curie point (resistance temperature change rate), it is necessary to add Mn at a predetermined ratio to a barium titanate-based semiconductor ceramic composition. Are known.
【０００６】 また、常温における比抵抗を小さく、かつ、安定にす
るために、チタン酸バリウム系半導体磁器組成物にSiO2
を添加することが知られている。Further, in order to make the specific resistance at room temperature small and stable, a barium titanate-based semiconductor ceramic composition is made of SiO 2.
It is known to add
【０００７】 そして、こうしたチタン酸バリウム系半導体磁器組成
物の耐電圧特性を向上させるために、BaTiO3のBaの一部
をCaで、またはCa及びSrで置換し、さらに、添加剤とし
てマンガン、シリカを添加含有させたチタン酸バリウム
系半導体磁器組成物が提案されている。しかし、このチ
タン酸バリウム系半導体磁器組成物においては、CaTiO3
の割合が３モル％以上、SrTiO3の割合が１モル％以上、
PbTiO3の割合が１モル％以上であることから、比抵抗を
10Ω・cm以下にすると耐電圧（絶縁破壊電圧）を100V/m
m以上とすることができないため、種々の優れた特性を
有しているにもかかわらず、その用途が制約されるとい
う問題点がある。In order to improve the withstand voltage characteristics of such a barium titanate-based semiconductor porcelain composition, Ba of BaTiO 3 is partially replaced with Ca or with Ca and Sr, and manganese is further added as an additive. There has been proposed a barium titanate-based semiconductor porcelain composition containing silica. However, in this barium titanate-based semiconductor ceramic composition, CaTiO 3
Is 3 mol% or more, the ratio of SrTiO 3 is 1 mol% or more,
Since the ratio of PbTiO 3 is 1 mol% or more, the specific resistance
When the resistance is 10Ωcm or less, the withstand voltage (dielectric breakdown voltage) is 100V / m
Since it cannot be more than m, there is a problem that its use is restricted despite having various excellent characteristics.
【０００８】 この発明は、上記問題点を解決するものであり、耐電
圧特性に優れ（100V/mm以上150V/mm以下）、かつ、比抵
抗の小さい（10Ω・cm以下）チタン酸バリウム系半導体
磁器組成物を提供することを目的とする。The present invention solves the above-mentioned problems, and is a barium titanate-based semiconductor having excellent withstand voltage characteristics (100 V / mm or more and 150 V / mm or less) and low specific resistance (10 Ω · cm or less). It is an object to provide a porcelain composition.
【０００９】[0009]
この発明のチタン酸バリウム系半導体磁器組成物は、
チタン酸バリウム系の主成分に、マンガン、シリカ及び
半導体化剤を添加含有させたチタン酸バリウム系半導体
磁器組成物において、 前記主成分は、BaTiO3、SrTiO3、CaTiO3及びPbTiO
3を： 65モル％≦BaTiO3≦95モル％ １モル％≦SrTiO3≦25モル％ ２モル％＜CaTiO3≦25モル％ 0.01モル％≦PbTiO3＜１モル％ の割合で含有してなり、 比抵抗が10Ω・cm以下であり、かつ、耐電圧が100V/m
m以上150V/mm以下であることを特徴とする。The barium titanate-based semiconductor porcelain composition of the present invention comprises:
In a barium titanate-based main component, manganese, silica and a semiconducting agent are added and contained in a barium titanate-based semiconductor porcelain composition, wherein the main component is BaTiO 3 , SrTiO 3 , CaTiO 3 and PbTiO.
3 : 65 mol% ≦ BaTiO 3 ≦ 95 mol% 1 mol% ≦ SrTiO 3 ≦ 25 mol% 2 mol% <CaTiO 3 ≦ 25 mol% 0.01 mol% ≦ PbTiO 3 <1 mol% , The specific resistance is 10Ωcm or less, and the withstand voltage is 100V / m
It is characterized by being not less than m and not more than 150 V / mm.
【００１０】 この発明のチタン酸バリウム系半導体磁器組成物の主
成分は、BaTiO3、SrTiO3、CaTiO3及びPbTiO3を上記の割
合で含有してなるものである。The main component of the barium titanate-based semiconductor porcelain composition of the present invention contains BaTiO 3 , SrTiO 3 , CaTiO 3 and PbTiO 3 in the above proportions.
【００１１】 PbTiO3、SrTiO3は単独ではキュリー点をそれぞれ高温
側、低音側に移行させるものであることが知られている
が、SrTiO3、CaTiO3及びPbTiO3を主成分の一部としてBa
TiO3に含有させることにより、耐電圧値が向上するとい
う効果がある。[0011] PbTiO 3, SrTiO 3 alone, respectively high-temperature side of the Curie point, is known to be one which shifts the bass side, Ba and SrTiO 3, CaTiO 3 and PbTiO 3 as part of the main component
By containing TiO 3 , there is an effect that the withstand voltage value is improved.
【００１２】 この発明のチタン酸バリウム系半導体磁器組成物にお
いて、主成分中のBaTiO3の配合割合を65〜95モル％とし
たのは、BaTiO3が65モル％未満である場合には半導体化
が困難で、かつ比抵抗も大きくなり、また、95モル％を
越えると電気的特性が著しく低下するからである。In the barium titanate-based semiconductor porcelain composition of the present invention, the mixing ratio of BaTiO 3 in the main component is set to 65 to 95 mol% because when BaTiO 3 is less than 65 mol%, the compound is converted to a semiconductor. This is because it is difficult to increase the specific resistance, and when it exceeds 95 mol%, the electrical characteristics are remarkably deteriorated.
【００１３】 また、SrTiO3の割合を１〜25モル％としたのは、SrTi
O3が１モル％未満では、特性改善の効果がなく、また、
25モル％を上回ると電気的特性が劣化するからである。The reason why the ratio of SrTiO 3 is set to 1 to 25 mol% is that SrTi 3
When O 3 is less than 1 mol%, there is no effect of improving properties, and
If the content exceeds 25 mol%, the electrical characteristics deteriorate.
【００１４】 さらに、CaTiO3の配合割合を ２モル％＜CaTiO3≦25モル％ としたのは、CaTiO3が２モル％以下では、特性改善の効
果が認められず、また25モル％を越えると電気的特性が
劣化するからである。Further, the reason that the mixing ratio of CaTiO 3 is set to 2 mol% <CaTiO 3 ≦ 25 mol% is that when CaTiO 3 is 2 mol% or less, no effect of improving properties is observed, and more than 25 mol% This is because electrical characteristics deteriorate.
【００１５】 また、PbTiO3の配合割合を 0.01モル％≦PbTiO3＜１モル％ としたのは、PbTiO3が0.01モル％未満では、特性改善の
効果が十分ではないが、0.01モル％以上であれば、上記
他の主成分との関係において１モル％未満でも所望の効
果が得られるからである。Further, the reason why the mixing ratio of PbTiO 3 is set to 0.01 mol% ≦ PbTiO 3 <1 mol% is that when the content of PbTiO 3 is less than 0.01 mol%, the effect of improving the characteristics is not sufficient. If so, the desired effect can be obtained even with less than 1 mol% in relation to the other main components.
【００１６】 また、この発明のチタン酸バリウム系半導体磁器組成
物は半導体化のために、半導体化剤を添加しているが、
この半導体化剤としては、Ｙ、La、Ceなどの希土類元
素、Nb、Bi、Sb、Ｗ、Thなどの元素が例示される。そし
て、これらの元素のうち少なくとも１種を添加するが、
その添加量は、比抵抗を小さくする見地から0.2〜1.0モ
ル％の範囲であることが望ましい。The barium titanate-based semiconductor porcelain composition of the present invention contains a semiconducting agent for conversion to a semiconductor.
Examples of the semiconducting agent include rare earth elements such as Y, La, and Ce, and elements such as Nb, Bi, Sb, W, and Th. Then, at least one of these elements is added,
The amount added is desirably in the range of 0.2 to 1.0 mol% from the viewpoint of reducing the specific resistance.
【００１７】 さらに、添加剤としてマンガン（MnCO3等）を微量添
加するが、これは、マンガンを添加しMnO2として含有さ
せることにより、キュリー点を越えた後の正の抵抗温度
特性において、抵抗温度変化率を増大させるためであ
る。その添加量はMnとして0.03から0.10モル％の範囲で
あることが、常温における抵抗を過度に高くすることな
く必要な添加効果を得るために好ましい。Further, a small amount of manganese (such as MnCO 3 ) is added as an additive. This is because manganese is added and contained as MnO 2 , so that the positive resistance temperature characteristic after the temperature exceeds the Curie point is reduced. This is for increasing the temperature change rate. The addition amount is preferably in the range of 0.03 to 0.10 mol% as Mn in order to obtain a necessary addition effect without excessively increasing the resistance at room temperature.
【００１８】 さらに、半導体化剤の添加量のわずかな変動によって
生じる比抵抗の変化を抑制し、常温における低い比抵抗
を得るためにシリカ（SiO2）を添加するが、その添加量
はSiO2として0.5〜５モル％の範囲であることが好まし
い。Furthermore, the change in the specific resistance is suppressed caused by slight variations in the added amount of the semiconductor agents, although the addition of silica (SiO 2) to obtain a low specific resistance at room temperature, the addition amount of SiO 2 Is preferably in the range of 0.5 to 5 mol%.
【００１９】[0019]
以下に、この発明の実施例及び比較例を示して発明を
さらに詳細に説明する。Hereinafter, the present invention will be described in more detail by showing Examples and Comparative Examples of the present invention.
【００２０】 ［実施例］ 主成分となるBaCO3、SrCO3、CaCO3、Pb3O4、TiO2、半
導体化剤であるY2O3、添加剤であるMnCO3、SiO2を、第
１表に示す組成のチタン酸バリウム系半導体磁器組成物
が得られるような割合で配合し、湿式混合した。これ
を、脱水、乾燥し、1150℃で２時間仮焼して仮焼原料を
得た。それから、得られた仮焼原料を粉砕し、さらにバ
インダを加えて造粒し、成形圧力1000kg/cm2で成形して
円板状の成形体を得た。そして、得られた成形体を1360
℃で1.5時間焼成し、直径17.5mm、厚さ0.6mmの円板状の
半導体磁器を得た。Example BaCO 3 , SrCO 3 , CaCO 3 , Pb 3 O 4 , TiO 2 , Y 2 O 3 as a semiconducting agent, MnCO 3 and SiO 2 as additives are The barium titanate-based semiconductor porcelain compositions having the compositions shown in Table 1 were blended in such a ratio as to obtain them and were wet-mixed. This was dehydrated, dried, and calcined at 1150 ° C. for 2 hours to obtain a calcined raw material. Then, the obtained calcined raw material was pulverized, granulated by further adding a binder, and molded at a molding pressure of 1000 kg / cm 2 to obtain a disk-shaped molded body. Then, the obtained molded body is 1360
C. for 1.5 hours to obtain a disc-shaped semiconductor porcelain having a diameter of 17.5 mm and a thickness of 0.6 mm.
【００２１】 ［比較例］ 比較のため、上記実施例で用いた各原料を用い、配合
割合を変えて、この発明のチタン酸バリウム系半導体磁
器組成物の範囲外の組成とし、その他は、上記実施例と
同様の手順、条件でチタン酸バリウム系半導体磁器組成
物を製造した。[Comparative Example] For comparison, the respective raw materials used in the above examples were used, and the mixing ratio was changed so that the composition was out of the range of the barium titanate-based semiconductor ceramic composition of the present invention. A barium titanate-based semiconductor ceramic composition was manufactured in the same procedure and under the same conditions as in the example.
【００２２】 上記実施例及び比較例のチタン酸バリウム系半導体磁
器について、両主面にIn−Ga合金の電極を形成し、これ
を試料として常温（25℃）における比抵抗、耐電圧特性
を測定した。その結果を第１表に示す。With respect to the barium titanate-based semiconductor porcelains of the above Examples and Comparative Examples, electrodes of an In—Ga alloy were formed on both main surfaces, and the samples were used as samples to measure the specific resistance and withstand voltage characteristics at room temperature (25 ° C.). did. Table 1 shows the results.
【００２３】 なお、第１表において試料番号に＊印を付したものは
比較例の試料であり、その他は全てこの発明の実施例に
よる試料である。In Table 1, those marked with an asterisk (*) are the samples of the comparative examples, and all others are samples according to the examples of the present invention.
【００２４】 また、第１表の比抵抗及び耐電圧の値は、下記の方法
により測定した値である。The values of specific resistance and withstand voltage in Table 1 are values measured by the following methods.
【００２５】 ［比抵抗］ 試料の抵抗値をデジタルマルチメータを用いて測定す
る。そして、得られた測定値から、式 ρ＝Ｒ×（S/L） により比抵抗を求める。[Specific Resistance] The resistance value of the sample is measured using a digital multimeter. Then, from the obtained measured values, the specific resistance is obtained by the equation ρ = R × (S / L).
【００２６】 但し、ρは比抵抗、Ｒは抵抗値、Ｓは表面積、Ｌは厚
みである。Here, ρ is a specific resistance, R is a resistance value, S is a surface area, and L is a thickness.
【００２７】 ［耐電圧］ 試料に10Vの電圧を２分間印加した後その電流値を測
定する。それから、さらに5V高い電圧を１分間印加した
後その電流値を測定する。上記のように前回より5V高い
電圧を印加する操作を繰り返し、測定した電流値が、前
回に測定した電流値よりも大きくなったときに、試料は
破壊点（TN点）に達したとして、一回前に印加した電圧
を耐電圧とする。[Withstand Voltage] After applying a voltage of 10 V to the sample for 2 minutes, the current value is measured. Then, a voltage higher by 5 V is applied for one minute, and the current value is measured. The operation of applying a voltage 5 V higher than the previous time is repeated as described above. When the measured current value becomes larger than the previously measured current value, it is determined that the sample has reached the breaking point (TN point). The voltage applied the last time is the withstand voltage.
【表１】 [Table 1]
【００２９】 第１表に示すように、比較例においては、比抵抗を低
く押えるように配合割合を調整したものは耐電圧が低
く、また、耐電圧を重視してこれを高めようとすると比
抵抗が大きくなるという特性上の問題点を含有している
ことがわかる。As shown in Table 1, in the comparative example, the withstand voltage was low when the compounding ratio was adjusted so as to keep the specific resistance low, and when the withstand voltage was emphasized, the withstand voltage was increased. It can be seen that there is a problem in characteristics that the resistance is increased.
【００３０】 これに対して、この発明の組成範囲内のチタン酸バリ
ウム系半導体磁器組成物は、耐電圧が100V/mm以上150V/
mm以下で、比抵抗が10Ω・cm以下と、耐電圧及び比抵抗
の両方の特性において優れていることがわかる。On the other hand, the barium titanate-based semiconductor ceramic composition within the composition range of the present invention has a withstand voltage of 100 V / mm or more and 150 V / mm or more.
mm, the specific resistance is 10 Ω · cm or less, which indicates that both the withstand voltage and the specific resistance are excellent.
【００３１】[0031]
この発明のチタン酸バリウム系半導体磁器組成物は、
BaTiO3、SrTiO3、CaTiO3、PbTiO3を所定の割合で含有す
る主成分に、添加剤と半導体化剤とを添加含有させ、比
抵抗を10Ω・cm以下、かつ、耐電圧特性を100V/mm以上1
50V/mm以下としたものであり、比抵抗が小さく、かつ、
耐電圧特性にも優れ、温度制御用素子、電流制御用素子
その他種々の用途に低く用いることができる。The barium titanate-based semiconductor porcelain composition of the present invention comprises:
BaTiO 3 , SrTiO 3 , CaTiO 3 , PbTiO 3 are added to a main component containing at a predetermined ratio, an additive and a semiconducting agent are added, and the specific resistance is 10 Ωcm or less, and the withstand voltage characteristic is 100 V / mm or more 1
50 V / mm or less, low specific resistance, and
It has excellent withstand voltage characteristics and can be used low for temperature control elements, current control elements and other various applications.
Claims (1)
ン、シリカ及び半導体化剤を添加含有させたチタン酸バ
リウム系半導体磁器組成物において、 前記主成分は、BaTiO3、SrTiO3、CaTiO3及びPbTiO3を： 65モル％≦BaTiO3≦95モル％ １モル％≦SrTiO3≦25モル％ ２モル％＜CaTiO3≦25モル％ 0.01モル％≦PbTiO3＜１モル％ の割合で含有してなり、 比抵抗が10Ω・cm以下であり、かつ、耐電圧が100V/mm
以上150V/mm以下であることを特徴とするチタン酸バリ
ウム系半導体磁器組成物。1. A barium titanate-based semiconductor porcelain composition comprising a barium titanate-based main component and manganese, silica and a semiconducting agent added thereto, wherein the main components are BaTiO 3 , SrTiO 3 , CaTiO 3 and PbTiO 3 : 65 mol% ≦ BaTiO 3 ≦ 95 mol% 1 mol% ≦ SrTiO 3 ≦ 25 mol% 2 mol% <CaTiO 3 ≦ 25 mol% 0.01 mol% ≦ PbTiO 3 <1 mol% The specific resistance is 10Ωcm or less and the withstand voltage is 100V / mm
A barium titanate-based semiconductor porcelain composition characterized by being at least 150 V / mm or less.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29664190A JP3273468B2 (en) | 1990-10-31 | 1990-10-31 | Barium titanate-based semiconductor porcelain composition |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29664190A JP3273468B2 (en) | 1990-10-31 | 1990-10-31 | Barium titanate-based semiconductor porcelain composition |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04170360A JPH04170360A (en) | 1992-06-18 |
| JP3273468B2 true JP3273468B2 (en) | 2002-04-08 |
Family
ID=17836168
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|---|---|---|---|
| JP29664190A Expired - Lifetime JP3273468B2 (en) | 1990-10-31 | 1990-10-31 | Barium titanate-based semiconductor porcelain composition |
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1990
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