JP2940182B2 - Method for manufacturing semiconductor porcelain having positive temperature coefficient of resistance - Google Patents
Method for manufacturing semiconductor porcelain having positive temperature coefficient of resistanceInfo
- Publication number
- JP2940182B2 JP2940182B2 JP3177191A JP3177191A JP2940182B2 JP 2940182 B2 JP2940182 B2 JP 2940182B2 JP 3177191 A JP3177191 A JP 3177191A JP 3177191 A JP3177191 A JP 3177191A JP 2940182 B2 JP2940182 B2 JP 2940182B2
- Authority
- JP
- Japan
- Prior art keywords
- resistance
- temperature
- semiconductor porcelain
- temperature coefficient
- positive temperature
- 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 - Lifetime
Links
Description
【０００１】[0001]
【産業上の利用分野】この発明は、正の抵抗温度係数を
有するチタン酸バリウム（ＢａＴｉＯ3）系半導体磁器
の製造方法に関し、特にＰｂを含有する半導体磁器を低
抵抗化することが可能な製造方法に関する。BACKGROUND OF THE INVENTION This invention relates to a method for producing a positive barium titanate having a temperature coefficient of resistance (BaTiO 3) based semiconductor ceramic, which can particularly reduce the resistance of the semiconductive ceramic containing Pb production About the method.
【０００２】[0002]
【従来の技術】近年、大きな正の抵抗温度係数を有する
チタン酸バリウム（ＢａＴｉＯ3）系半導体磁器が開発
されており、キュリー温度を越えると抵抗値が急激に増
大して、通過する電流量を減少させることから、回路の
過電流保護用や、テレビ受像機のブラウン管枠の消磁用
などの用途に広く用いられている。このキュリー温度は
Ｂａの一部をＳｒなどで置換すると低温側に変化し、Ｐ
ｂなどで置換することにより高温側に変化させることが
できることから、用途に応じてこれらの元素を添加して
キュリー温度を調整している。2. Description of the Related Art In recent years, barium titanate (BaTiO 3 ) -based semiconductor porcelains having a large positive temperature coefficient of resistance have been developed. Because of the reduction, it is widely used for applications such as overcurrent protection of circuits and degaussing of CRT frames of television receivers. This Curie temperature changes to a low temperature side when a part of Ba is replaced with Sr or the like, and P
Since it can be changed to a higher temperature side by substituting with b or the like, the Curie temperature is adjusted by adding these elements according to the application.
【０００３】一方、このチタン酸バリウム系半導体磁器
を用いた素子を小型化し、あるいは大電流化するため
に、室温抵抗の低減を望む声が強い。そして、このよう
な要望に応えるものとして、Ｐｂを含むチタン酸バリウ
ム系半導体磁器の製造方法に関して、焼成体を還元雰囲
気中や、中性雰囲気中で焼成する方法、あるいは還元処
理して抵抗を低減した後、再酸化する方法が提案されて
いる。On the other hand, in order to reduce the size or increase the current of an element using the barium titanate-based semiconductor porcelain, there is a strong demand for a reduction in room temperature resistance. In response to such a demand, a method for producing a barium titanate-based semiconductor porcelain containing Pb includes a method of firing a fired body in a reducing atmosphere or a neutral atmosphere, or a method of reducing the resistance by performing a reduction treatment. After re-oxidation, a method has been proposed.
【０００４】[0004]
【発明が解決しようとする課題】しかし、チタン酸バリ
ウム系半導体磁器がＰｂを含む場合、還元性雰囲気や中
性雰囲気でこれを焼成したり、単に還元・再酸化処理す
るのみでは、磁器中のＰｂが還元されて蒸発し、組成が
変化して室温抵抗が著しく高くなり、実用上支障をきた
すという問題点がある。However, when the barium titanate-based semiconductor porcelain contains Pb, the sintering of the porcelain in a reducing atmosphere or a neutral atmosphere, or a simple reduction / re-oxidation treatment, is not sufficient. There is a problem that Pb is reduced and evaporated, the composition is changed, and the room temperature resistance is significantly increased, which causes a practical problem.
【０００５】この発明は、上記問題点を解決するもので
あり、Ｐｂを含有する、低抵抗のチタン酸バリウム系半
導体磁器の製造方法を提供することを目的とする。An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a method for producing a low-resistance barium titanate-based semiconductor ceramic containing Pb.
【０００６】[0006]
【課題を解決するための手段及び作用】上記目的を達成
するために、この発明の正の抵抗温度係数を有する半導
体磁器の製造方法は、Ｂａの一部をＰｂで置換したチタ
ン酸バリウム系半導体磁器原料の成形体を空気中で焼成
した後、１１５０〜１２５０℃の温度条件下で還元処理
し、さらに、酸化性雰囲気中で熱処理することを特徴と
する。この発明は、焼成や還元処理の際の圧力や水素分
圧などの雰囲気、焼成温度パターン、還元処理の温度及
び時間などを種々検討することによりなされたものであ
り、チタン酸バリウム系の正特性半導体磁器原料の成形
体を空気中で焼成した後、上記温度範囲で還元処理し、
さらに、酸化性雰囲気中で熱処理することにより、Ｐｂ
を含む半導体磁器の室温抵抗を十分に低減することが可
能になる。なお、還元処理温度が１２５０℃を越えると
室温抵抗が上昇してしまい、また、１１５０℃未満では
還元時に抵抗が低下するが、その後の酸化性雰囲気中で
の熱処理によりキュリー温度での十分な抵抗変化率が得
られないため、還元処理温度は１１５０〜１２５０℃の
範囲にあることが好ましい。In order to achieve the above object, a method of manufacturing a semiconductor ceramic having a positive temperature coefficient of resistance according to the present invention is directed to a barium titanate-based semiconductor wherein Ba is partially substituted with Pb. After firing the formed body of the porcelain material in the air, a reduction treatment is performed under a temperature condition of 1150 to 1250 ° C., and further, a heat treatment is performed in an oxidizing atmosphere. The present invention was made by variously examining atmospheres such as pressure and hydrogen partial pressure at the time of calcination and reduction treatment, calcination temperature pattern, temperature and time of reduction treatment, and the like. After firing the molded body of the semiconductor porcelain raw material in the air, reduction treatment in the above temperature range,
Further, by performing heat treatment in an oxidizing atmosphere, Pb
, It is possible to sufficiently reduce the room temperature resistance of the semiconductor porcelain containing. If the temperature of the reduction treatment exceeds 1250 ° C., the resistance at room temperature increases, and if it is less than 1150 ° C., the resistance decreases at the time of reduction. Since the rate of change cannot be obtained, the reduction treatment temperature is preferably in the range of 1150 to 1250 ° C.
【０００７】[0007]
【実施例】以下に、この発明の実施例及び比較例を示し
て発明の特徴をさらに詳細に説明する。The features of the present invention will be described below in more detail with reference to examples and comparative examples of the present invention.
【０００８】まず、ＢａＣＯ3，ＴｉＯ2，Ｐｂ3Ｏ4，Ｙ
2Ｏ3，Ｍｎ2Ｏ3，ＳｉＯ2のそれぞれを下記の式(1)： （Ｂａ0.896Ｐｂ0.10Ｙ0.004）ＴｉＯ3＋0.001Ｍｎ＋0.01ＳｉＯ2 (1) で表される所定の組成になるような割合で混合する。そ
して、これを純水及びジルコニアボールとともにポリエ
チレン製ポットに入れて５時間粉砕混合した後、１１０
０℃で２時間仮焼する。この仮焼粉に酢酸ビニル系のバ
インダ５重量％を添加して混合し、純水とメノウボール
とともにポリエチレン製ポット中で５時間粉砕混合し、
乾燥造粒する。これをプレス成形機により成形して、直
径１７mm，厚さ３mmの円板状の成形体を作成し、この成
形体を１３５０℃で１時間焼成する。この焼成体を（Ｈ
2／Ｎ2）＝０．０５（容量比）の雰囲気中で２時間還元
焼成した後、大気中で２時間熱処理して再酸化処理を行
った。還元処理温度は１１００〜１３００℃の範囲で変
化させ、再酸化処理温度は８００〜１２００℃の範囲で
変化させた。このようにして得られた焼成体（半導体磁
器）の両主面にＩｎ−Ｇａ合金を塗布して電極を形成
し、これを試料として温度と抵抗の関係を調べた。First, BaCO 3 , TiO 2 , Pb 3 O 4 , Y
Each of 2 O 3 , Mn 2 O 3 , and SiO 2 has a predetermined composition represented by the following formula (1): (Ba 0.896 Pb 0.10 Y 0.004 ) TiO 3 +0.001 Mn + 0.01 SiO 2 (1) Mix in proper proportions. Then, this was put in a polyethylene pot together with pure water and zirconia balls and pulverized and mixed for 5 hours.
Calcinate at 0 ° C for 2 hours. 5% by weight of a vinyl acetate binder is added to and mixed with the calcined powder, and ground and mixed together with pure water and agate ball in a polyethylene pot for 5 hours.
Dry and granulate. This is molded by a press molding machine to produce a disk-shaped molded body having a diameter of 17 mm and a thickness of 3 mm, and this molded body is fired at 1350 ° C. for 1 hour. This fired body is (H
After reduction firing in an atmosphere of ( 2 / N 2 ) = 0.05 (volume ratio) for 2 hours, heat treatment was performed in the air for 2 hours to perform reoxidation. The reduction treatment temperature was changed in the range of 1100 to 1300 ° C, and the reoxidation treatment temperature was changed in the range of 800 to 1200 ° C. An In-Ga alloy was applied to both main surfaces of the fired body (semiconductor porcelain) thus obtained to form an electrode, and the relationship between temperature and resistance was examined using the electrode as a sample.
【０００９】図１〜図５に、それぞれ還元処理温度１１
００℃、１１５０℃、１２００℃、１２５０℃、１３０
０℃で還元処理した場合の比抵抗と温度の関係（抵抗温
度曲線）を示す。また、これらの図から、室温比抵抗と
キュリー温度での抵抗変化率（最高比抵抗ρmax／室温
比抵抗ρ25）の関係を調べた結果を図６に示す。なお、
上記の還元処理温度１１００℃及び１３００℃はこの発
明の範囲外であり、比較例である。FIG. 1 to FIG.
00 ° C, 1150 ° C, 1200 ° C, 1250 ° C, 130
The relationship between the specific resistance and the temperature when the reduction treatment is performed at 0 ° C (resistance temperature curve) is shown. FIG. 6 shows the results of examining the relationship between the room temperature resistivity and the rate of change in resistance at the Curie temperature (maximum resistivity ρ max / room temperature resistivity ρ 25 ) from these figures. In addition,
The above reduction treatment temperatures of 1100 ° C. and 1300 ° C. are out of the scope of the present invention and are comparative examples.
【００１０】これらの図に示すように、還元処理温度１
１００℃（比較例１）で還元処理した場合、処理後の室
温比抵抗は１Ω・cm（図４）と低いものの再酸化した場
合の抵抗変化率の上昇が小さく、キュリー温度での抵抗
変化率（ρmax／ρ25）の値が実用上必要とされる数百
になるまで再酸化すると、室温比抵抗が約２５Ω・cmに
まで上昇してしまう。（図６）。As shown in these figures, as shown in FIG.
When the reduction treatment was performed at 100 ° C. (Comparative Example 1), although the room temperature resistivity after the treatment was as low as 1 Ω · cm (FIG. 4), the increase in the resistance change rate when reoxidized was small, and the resistance change rate at the Curie temperature was small. If reoxidation is performed until the value of (ρ max / ρ 25 ) reaches several hundreds required for practical use, the room temperature resistivity increases to about 25 Ω · cm. (FIG. 6).
【００１１】また、還元処理温度１３００℃（比較例
２）で還元処理した場合、還元後（再酸化前）において
もその室温比抵抗が約５Ω・cmと高く（図５）、また、
キュリー温度での抵抗変化率（ρmax／ρ25）の値が数
百になるまで再酸化すると、室温比抵抗が約５０Ω・cm
にまで上昇してしまい（図６）、好ましい特性を得るこ
とができない。When the reduction treatment is performed at a reduction treatment temperature of 1300 ° C. (Comparative Example 2), the room temperature resistivity after the reduction (before re-oxidation) is as high as about 5 Ω · cm (FIG. 5).
Reoxidation until the value of the rate of change of resistance (ρ max / ρ 25 ) at the Curie temperature reaches several hundreds gives a room temperature specific resistance of about 50 Ω · cm.
(FIG. 6), which makes it impossible to obtain desirable characteristics.
【００１２】一方、本発明の範囲内の還元処理温度１１
５０℃（実施例１）、１２００℃（実施例２）、１２５
０℃（実施例３）で還元処理した場合、図１〜図３に示
すように、処理後の室温比抵抗が、それぞれ０．７Ω・
cm、０．５Ω・cm、０．９Ω・cmと低く、さらに、再酸
化した場合の抵抗変化率の上昇も早い。そして、キュリ
ー温度での抵抗変化率（ρmax／ρ25）の値が実用上必
要とされる数百を越えるまで再酸化した場合の室温比抵
抗はそれぞれ６．２Ω・cm、４．０Ω・cm、６．７Ω・
cmと極めて低い値であり、好ましい特性を得ることがで
きた。On the other hand, a reduction treatment temperature 11 within the range of the present invention.
50 ° C. (Example 1), 1200 ° C. (Example 2), 125
When the reduction treatment was performed at 0 ° C. (Example 3), as shown in FIGS. 1 to 3, the room temperature resistivity after the treatment was 0.7Ω ·
cm, 0.5 Ω · cm, and 0.9 Ω · cm, and the rate of change in resistance when reoxidized is fast. Then, when re-oxidized until the value of the resistance change rate (ρ max / ρ 25 ) at the Curie temperature exceeds several hundreds required for practical use, the room temperature specific resistances are 6.2 Ω · cm and 4.0 Ω · cm, 6.7Ω
cm, which is an extremely low value, and favorable characteristics could be obtained.
【００１３】[0013]
【発明の効果】上述のように、この発明の正の抵抗温度
係数を有する半導体磁器の製造方法は、チタン酸バリウ
ム系正特性半導体磁器原料の成形体を空気中で焼成した
後、１１５０〜１２５０℃の温度条件下で還元処理し、
さらに、酸化性雰囲気中で熱処理するように構成してい
るので、正の抵抗温度特性を有するチタン酸バリウム系
半導体磁器の室温比抵抗を大幅に低減することができ
る。As described above, the method for manufacturing a semiconductor porcelain having a positive temperature coefficient of resistance according to the present invention comprises the steps of firing a molded body of barium titanate-based positive characteristic semiconductor porcelain in air, and then arranging 1150 to 1250. Reduction treatment under temperature condition of ℃,
Further, since the heat treatment is performed in an oxidizing atmosphere, the room temperature specific resistance of the barium titanate-based semiconductor porcelain having a positive resistance temperature characteristic can be significantly reduced.
【図１】実施例１の比抵抗と温度の関係（抵抗温度曲
線）を示す図である。FIG. 1 is a diagram showing a relationship between specific resistance and temperature (resistance temperature curve) in Example 1.
【図２】実施例２の比抵抗と温度の関係（抵抗温度曲
線）を示す図である。FIG. 2 is a diagram showing the relationship between specific resistance and temperature (resistance temperature curve) in Example 2.
【図３】実施例３の比抵抗と温度の関係（抵抗温度曲
線）を示す図である。FIG. 3 is a diagram showing a relationship between specific resistance and temperature (resistance temperature curve) in Example 3.
【図４】比較例１の比抵抗と温度の関係（抵抗温度曲
線）を示す図である。FIG. 4 is a diagram showing a relationship between specific resistance and temperature (resistance temperature curve) of Comparative Example 1.
【図５】比較例２の比抵抗と温度の関係（抵抗温度曲
線）を示す図である。FIG. 5 is a diagram showing a relationship between specific resistance and temperature (resistance temperature curve) of Comparative Example 2.
【図６】室温比抵抗とキュリー温度での抵抗変化率（最
高比抵抗ρmax／室温比抵抗ρ25）の関係を示す図であ
る。6 is a diagram showing the relationship between resistance change rate at room temperature resistivity and Curie temperature (maximum resistivity [rho max / room temperature resistivity ρ 2 5).
Claims (1)
リウム系半導体磁器原料の成形体を空気中で焼成した
後、１１５０〜１２５０℃の温度条件下で還元処理し、
さらに、酸化性雰囲気中で熱処理することを特徴とする
正の抵抗温度係数を有する半導体磁器の製造方法。1. A molded body of a barium titanate-based semiconductor porcelain raw material in which a part of Ba is substituted with Pb is fired in air, and then reduced under a temperature condition of 1150 to 1250 ° C.
Furthermore, a method for manufacturing a semiconductor ceramic having a positive temperature coefficient of resistance, characterized by performing a heat treatment in an oxidizing atmosphere.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3177191A JP2940182B2 (en) | 1991-01-30 | 1991-01-30 | Method for manufacturing semiconductor porcelain having positive temperature coefficient of resistance |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3177191A JP2940182B2 (en) | 1991-01-30 | 1991-01-30 | Method for manufacturing semiconductor porcelain having positive temperature coefficient of resistance |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04245401A JPH04245401A (en) | 1992-09-02 |
| JP2940182B2 true JP2940182B2 (en) | 1999-08-25 |
Family
ID=12340317
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3177191A Expired - Lifetime JP2940182B2 (en) | 1991-01-30 | 1991-01-30 | Method for manufacturing semiconductor porcelain having positive temperature coefficient of resistance |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2940182B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001130957A (en) * | 1999-11-02 | 2001-05-15 | Murata Mfg Co Ltd | Semiconductor ceramic, method for producing semiconductor ceramic, and thermistor |
-
1991
- 1991-01-30 JP JP3177191A patent/JP2940182B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04245401A (en) | 1992-09-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP2940182B2 (en) | Method for manufacturing semiconductor porcelain having positive temperature coefficient of resistance | |
| JP3166787B2 (en) | Barium titanate-based semiconductor porcelain composition | |
| JP3039511B2 (en) | Semiconductor ceramic and semiconductor ceramic element | |
| JP4779466B2 (en) | Barium titanate semiconductor porcelain composition | |
| JP2588951B2 (en) | High temperature PTC thermistor and manufacturing method thereof | |
| JP2689439B2 (en) | Grain boundary insulation type semiconductor porcelain body | |
| JP2679449B2 (en) | Semiconductor porcelain having positive temperature coefficient of resistance and manufacturing method thereof | |
| JPH07220902A (en) | Barium titanate semiconductor ceramic | |
| JPH0338802A (en) | Manufacture of positive temperature coefficient semiconductor porcelain | |
| JPH11102802A (en) | Positive temperature coefficient thermistor and its manufacture | |
| JP3598177B2 (en) | Voltage non-linear resistor porcelain | |
| JPH05198406A (en) | Barium titanate based semiconductor porcelain composition | |
| JPH04154661A (en) | Semiconductor porcelain and its production | |
| JPH11139870A (en) | Barium titanate-base semiconductor porcelain | |
| JP4800956B2 (en) | Barium titanate semiconductor porcelain composition | |
| JPH04311002A (en) | Manufacture of semiconductor porcelain with positive temperature coefficient of resistance | |
| JP2677041B2 (en) | Semiconductor porcelain with positive temperature coefficient of resistance | |
| JPH03215354A (en) | Barium titanate-based semiconductor ceramic composition | |
| JP3036051B2 (en) | Barium titanate-based semiconductor porcelain composition | |
| JPH1070007A (en) | Manufacture of positive temperature coefficient thermistor | |
| JPH1092604A (en) | Positive temperature coefficient thermistor and its manufacture | |
| JPH0684605A (en) | Positive characteristic thermister and production thereof | |
| JPH0684606A (en) | Production of positive characteristic thermister | |
| JPH0645104A (en) | Manufacture of semiconductor procelain with positive temperature coefficient of resistance | |
| JPH08162301A (en) | Semiconductor porcelain having positive resistance temperature characteristic |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 19990518 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080618 Year of fee payment: 9 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090618 Year of fee payment: 10 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090618 Year of fee payment: 10 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100618 Year of fee payment: 11 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110618 Year of fee payment: 12 |
|
| EXPY | Cancellation because of completion of term | ||
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110618 Year of fee payment: 12 |