JPH0510802B2 - - Google Patents
Info
- Publication number
- JPH0510802B2 JPH0510802B2 JP58242834A JP24283483A JPH0510802B2 JP H0510802 B2 JPH0510802 B2 JP H0510802B2 JP 58242834 A JP58242834 A JP 58242834A JP 24283483 A JP24283483 A JP 24283483A JP H0510802 B2 JPH0510802 B2 JP H0510802B2
- Authority
- JP
- Japan
- Prior art keywords
- conductive layer
- varistor
- varistor body
- ohmic contact
- gap
- 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
- 229910052709 silver Inorganic materials 0.000 claims description 14
- 239000004332 silver Substances 0.000 claims description 14
- 230000002093 peripheral effect Effects 0.000 claims description 13
- 239000000654 additive Substances 0.000 claims description 6
- 229910052751 metal Inorganic materials 0.000 claims description 6
- 239000002184 metal Substances 0.000 claims description 6
- 230000000996 additive effect Effects 0.000 claims description 3
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 32
- 239000011787 zinc oxide Substances 0.000 description 15
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 12
- 239000000853 adhesive Substances 0.000 description 10
- 230000001070 adhesive effect Effects 0.000 description 10
- 239000013078 crystal Substances 0.000 description 9
- 239000003990 capacitor Substances 0.000 description 8
- 230000006866 deterioration Effects 0.000 description 6
- 238000009792 diffusion process Methods 0.000 description 4
- 230000003647 oxidation Effects 0.000 description 4
- 238000007254 oxidation reaction Methods 0.000 description 4
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 3
- 230000002950 deficient Effects 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 238000007639 printing Methods 0.000 description 3
- VEALVRVVWBQVSL-UHFFFAOYSA-N strontium titanate Chemical compound [Sr+2].[O-][Ti]([O-])=O VEALVRVVWBQVSL-UHFFFAOYSA-N 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- WABPQHHGFIMREM-UHFFFAOYSA-N lead(0) Chemical compound [Pb] WABPQHHGFIMREM-UHFFFAOYSA-N 0.000 description 2
- 238000007650 screen-printing Methods 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 229910052787 antimony Inorganic materials 0.000 description 1
- 229910052793 cadmium Inorganic materials 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 229910052733 gallium Inorganic materials 0.000 description 1
- 229910052738 indium Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
- 229910052718 tin Inorganic materials 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
Landscapes
- Thermistors And Varistors (AREA)
Description
【発明の詳細な説明】
＜産業上の利用分野＞
本発明は、ZnO系焼結体を用いたバリスタに関
する。Detailed Description of the Invention <Industrial Application Field> The present invention relates to a varistor using a ZnO-based sintered body.
＜従来の技術＞
バリスタは印加電圧がその素子の持つバリスタ
電圧（制限電圧）を越える範囲で抵抗値が激減す
る特異な特性を有する。この特異性に着目し、バ
リスタは、音響機器に関連する小型直流モータの
ノイズ防止、リレー接点の保護、カラーテレビブ
ラウン管回路の放電吸収等の手段として広く利用
されている。<Prior Art> A varistor has a unique characteristic in that its resistance value decreases dramatically within a range where the applied voltage exceeds the varistor voltage (limiting voltage) of the element. Taking note of this specificity, varistors are widely used as means for noise prevention in small DC motors associated with audio equipment, protection of relay contacts, and discharge absorption in color TV cathode ray tube circuits.
バリスタとしては、焼結体の粒子間の接触面で
バリスタ特性を得るシリコンカーバイト（SiC）
系のもの、焼結体自身は直線性抵抗体であるがこ
れに付与される電極との接触状態によつてバリス
タ特性を得る酸化錫（SnO）系、酸化鉄
（Fe2O3）系のもの、及び焼結体自身がバリスタ
特性を有する酸化チタン（TiO2）系、チタン酸
ストロンチウム（SrTiO3）系もしくは酸化亜鉛
（ZnO）系のもの等が知られている。これらの内、
前二者は電極や焼結体成形等の製造上の困難性を
伴い、価格が高くなることや、非直線性の経時的
的劣化を招き易いこと、バリスタ電圧が高過ぎ、
小型直流モータのノイズ消去用等に不向きである
こと等の難点がある。これに対して、焼結体自体
がバリスタ特性を有するもの、例えば酸化チタン
（TiO2）系、チタン酸ストロンチウム（SrTiO3）
系及び酸化亜鉛（ZnO）系のバリスタにはこのよ
うな欠点がない。 Silicon carbide (SiC) is used as a varistor, which obtains varistor properties at the contact surface between particles of a sintered body.
The sintered body itself is a linear resistor, but it gains varistor characteristics depending on the contact state with the electrode applied to it. Titanium oxide (TiO 2 )-based, strontium titanate (SrTiO 3 )-based, or zinc oxide (ZnO)-based materials are known, and the sintered body itself has varistor properties. Among these,
The first two methods involve manufacturing difficulties such as electrodes and sintered body molding, resulting in higher costs, the tendency to cause deterioration of nonlinearity over time, and the varistor voltage being too high.
It has drawbacks such as being unsuitable for noise cancellation in small DC motors. On the other hand, the sintered body itself has varistor properties, such as titanium oxide (TiO 2 ), strontium titanate (SrTiO 3 ).
ZnO-based and zinc oxide (ZnO)-based varistors do not have such drawbacks.
バリスタ素体自体がバリスタ特性を有するバリ
スタにおいて、焼結体自身の持つバリスタ特性を
充分に発揮させるには、電極をバリスタ素体に対
してオーム性接触となるように形成しなければな
らい。そこで、従来は、第１図及び第２図に示す
ように、バリスタ素体１の面上に、オーム性接触
となる第１導電層２を被着形成すると共に、第１
導電層２の半田付け性及び密着強度を補うと共
に、酸化によるオーム性接触の劣化等を防止する
目的で、第１導電層２の上に第２導電層３を被着
形成した構造を取つていた。４及び５はリード
線、６は外装樹脂である。 In a varistor whose varistor body itself has varistor properties, in order to fully exhibit the varistor properties of the sintered body itself, the electrodes must be formed in ohmic contact with the varistor body. Therefore, conventionally, as shown in FIGS. 1 and 2, a first conductive layer 2 is deposited on the surface of the varistor body 1 to form an ohmic contact, and a first
In order to supplement the solderability and adhesion strength of the conductive layer 2 and to prevent deterioration of ohmic contact due to oxidation, a structure is adopted in which a second conductive layer 3 is deposited on the first conductive layer 2. was. 4 and 5 are lead wires, and 6 is an exterior resin.
第１導電層２は、製造工程での印刷位置ズレに
伴う電極面積の変動を防止するため、外周端全周
にバリスタ素体１の露出するギヤツプG1が生じ
るように、バリスタ素体１より小さい平面積とな
るように形成してある。また、第２導電層３にお
いても、同様の理由により、外周端全周に第１導
電層２の露出するギヤツプG2が生じるように、
第１導電層２より小さい平面積となるように形成
してある。 The first conductive layer 2 is formed from the varistor body 1 so that a gap G 1 is formed around the entire outer periphery of the varistor body 1 in order to prevent variations in the electrode area due to misalignment of printing positions during the manufacturing process. It is formed to have a small plane area. In addition, for the same reason, in the second conductive layer 3, a gap G 2 is formed around the entire outer circumferential edge where the first conductive layer 2 is exposed.
It is formed to have a smaller planar area than the first conductive layer 2.
＜発明が解決しようとする課題＞
ところが、バリスタ素体自体がバリスタ特性を
有するバリスタのうち、酸化チタン（TiO2）系、
チタン酸ストロンチウム（SrTiO3）系は、バリ
スタ素体の結晶がコンデンサ素体として用いられ
る場合と大差ないが、ZnO系バリスタは、バリス
タ素体１の結晶が、約100μｍ前後と一般のコン
デンサ素体の数倍〜数十倍も大きくなることがあ
る。このような焼結体に対して、オーム性接触と
なるように第１導電層２を形成しなければならな
いため、バリスタ素体１に対する第１導電層２の
接着力が弱く、例えば印刷塗布後の乾燥工程にお
いてさえ、簡単に剥離してしまうという難点があ
り、場合によつては70％程度の不良率となる等、
歩留りが非常に悪かつた。<Problems to be Solved by the Invention> However, among varistors whose varistor body itself has varistor properties, titanium oxide (TiO 2 )-based,
Strontium titanate (SrTiO 3 ) type is not much different from the case where the crystal of the varistor element is used as the capacitor element, but in the ZnO type varistor, the crystal of the varistor element 1 is about 100 μm, which is different from that of a general capacitor element. It can be several times to several tens of times larger. Since the first conductive layer 2 must be formed in ohmic contact with such a sintered body, the adhesion of the first conductive layer 2 to the varistor body 1 is weak, for example, after printing and coating. Even during the drying process, it has the disadvantage that it easily peels off, resulting in a defect rate of about 70% in some cases.
Yield was very poor.
第１導電層２の接着力を強化する方法として、
フリツト含有量を増加する方法が考えられるが、
ZnO系バリスタは、バリスタ素体１の結晶が約
100μｍ前後と大きいために、バリスタ素体１の
粒界へのフリツト拡散が増し、バリスタ特性が取
れなくなり、特性的に著しく限定されたものしか
得られないこと、信頼性が悪くなること等の問題
点を生じる。 As a method of strengthening the adhesive force of the first conductive layer 2,
One possible method is to increase the frit content, but
For ZnO-based varistors, the crystal of varistor body 1 is approximately
Because it is large, around 100 μm, the diffusion of flitts to the grain boundaries of the varistor body 1 increases, making it impossible to obtain varistor characteristics, resulting in problems such as extremely limited characteristics and poor reliability. produce a point.
そこで、本発明の課題は、上述する従来からの
問題点を解決し、バリスタ特性の劣化及び信頼性
の低下を来すことなく、バリスタ素体に対する電
極接着強度を増大させ、電極剥離を防止し、歩留
りを向上させ得るようにしたバリスタを提供する
ことである。 Therefore, an object of the present invention is to solve the above-mentioned conventional problems, increase the adhesive strength of electrodes to the varistor body, and prevent electrode peeling without causing deterioration of varistor characteristics or reduction in reliability. An object of the present invention is to provide a varistor that can improve yield.
＜課題を解決するための手段＞
上述した課題解決のため、本発明は、バリスタ
素体と、第１導電層と、第２導電層とを含むバリ
スタであつて、
前記バリスタ素体は、ZnO系焼結体でなり、前
記第１導電層は、銀を主成分とし、オーム性接触
化を助ける金属成分添加物及びフリツトを含み、
周囲に前記バリスタ素体の露出するギヤツプが生
じるように、前記バリスタ素体の面内に焼き付け
られ、前記バリスタ素体との間でオーム性接触を
構成しており、
前記第２導電層は、銀を主成分とし、フリツト
を含み、前記第１導電層より平面積が大きくなる
ように前記第１導電層の表面に付着されると共
に、周辺部が前記ギヤツプの部分で前記バリスタ
素体の表面に接着されている。<Means for Solving the Problems> In order to solve the above problems, the present invention provides a varistor including a varistor body, a first conductive layer, and a second conductive layer, wherein the varistor body is made of ZnO. The first conductive layer is made of a sintered body, and the first conductive layer contains silver as a main component and contains a metal component additive and frit to help make ohmic contact.
The second conductive layer is baked into the surface of the varistor body so as to create a gap around which the varistor body is exposed, and forms an ohmic contact with the varistor body; It is mainly composed of silver and includes frit, and is attached to the surface of the first conductive layer so that its planar area is larger than that of the first conductive layer, and the periphery of the gap is the surface of the varistor body. is glued to.
＜作用＞
第１導電層は、周辺にバリスタ素体の露出する
ギヤツプが生じるように、バリスタ素体の面内に
焼き付けられており、第２導電層は、フリツトを
含み、第１導電層より平面積が大きくなるように
第１導電層の表面に付着されると共に、周辺部が
ギヤツプの部分でバリスタ素体の表面に接着され
ているから、第２導電層の周辺部がギヤツプに付
着する部分で、接着強度が向上する。しかも、第
２導電層はオーム性接着電極として形成する必要
がなく、そのフリツト含有量を高め、バリスタ素
体に対する接着強度を高めることができる。この
ため、第２導電層によつてバリスタ素体に対する
第１導電層の接着強度を補強し、バリスタ素体の
結晶が、約100μｍ前後と一般のコンデンサ素体
の数倍〜数十倍も大きくなることのあるZnO系バ
リスタにおいて、電極剥離を防止し、不良率を低
減させ、歩留りを向上させることができる。<Function> The first conductive layer is baked into the plane of the varistor body so as to create a gap around the periphery where the varistor body is exposed, and the second conductive layer includes a frit and The second conductive layer is attached to the surface of the first conductive layer so as to have a large planar area, and the peripheral part is adhered to the surface of the varistor body at the gap, so that the peripheral part of the second conductive layer adheres to the gap. Adhesive strength is improved in some areas. Moreover, the second conductive layer does not need to be formed as an ohmic adhesive electrode, and its frit content can be increased to increase adhesive strength to the varistor body. For this reason, the adhesion strength of the first conductive layer to the varistor element is reinforced by the second conductive layer, and the crystal of the varistor element is approximately 100 μm, which is several times to several tens of times larger than a general capacitor element. In ZnO-based varistors, which can sometimes occur, electrode peeling can be prevented, the defective rate can be reduced, and the yield can be improved.
第１導電層は、バリスタ素体の面内に焼き付け
られ、バリスタ素体との間でオーム性接触を構成
しており、第２導電層は第１導電層の表面に付着
されているから、オーム性接触は第１導電層によ
つて得られ、第２導電層はバリスタ特性に直接に
は関与しない。しかも、第２導電層は、周辺部が
ギヤツプの部分でバリスタ素体の表面に接着され
るのみである。このため、第２導電層のフリツト
含有量を増大させ、接着強度を高めながら、バリ
スタ素体の結晶が、約100μｍ前後と一般のコン
デンサ素体の数倍〜数十倍も大きくなることのあ
るZnO系バリスタにおいて、フリツトの拡散によ
るバリスタ特性の劣化を防止できる。 The first conductive layer is baked into the plane of the varistor body and forms ohmic contact with the varistor body, and the second conductive layer is attached to the surface of the first conductive layer. The ohmic contact is obtained by the first conductive layer; the second conductive layer does not directly participate in the varistor properties. Furthermore, the second conductive layer is only bonded to the surface of the varistor body at the peripheral portion where the gap is formed. For this reason, while increasing the frit content of the second conductive layer and increasing the adhesive strength, the crystals of the varistor element may become approximately 100 μm, several times to several tens of times larger than a general capacitor element. In ZnO-based varistors, deterioration of varistor characteristics due to flit diffusion can be prevented.
第１導電層は、銀を主成分とし、オーム性接触
化を助ける金属成分添加物及びフリツトを含み、
バリスタ素体の面内に焼き付けられ、バリスタ素
体との間でオーム性接触を構成しているから、
ZnO系焼結体自身の持つバリスタ特性を充分に発
揮させることができる。 The first conductive layer is mainly composed of silver and includes a metal component additive and a frit to help form an ohmic contact,
Because it is baked into the surface of the varistor body and forms ohmic contact with the varistor body,
The varistor properties of the ZnO-based sintered body itself can be fully exhibited.
第２導電層は、半田付け性の良好な銀を主成分
としているから、リード線を確実に、かつ、強固
に半田付けでき、しかも、第１導電層によるオー
ム性接触を損なうことがない。 Since the second conductive layer is mainly composed of silver, which has good solderability, the lead wire can be soldered reliably and firmly without impairing the ohmic contact made by the first conductive layer.
第１導電層はバリスタ素体の面内に焼き付けら
れており、第２導電層は、第１導電層より平面積
が大きくなるように第１導電層の表面に付着され
ると共に、周辺部がギヤツプの部分でバリスタ素
体の表面に接着されているから、第１導電層の全
面を第２導電層によつて封止した構造となる。こ
のため、第１導電層の酸化が防止され、オーム性
接触が長期間に亘つて安定に保たれ、信頼性が向
上する。 The first conductive layer is baked into the plane of the varistor body, and the second conductive layer is attached to the surface of the first conductive layer so that its planar area is larger than that of the first conductive layer, and the peripheral part is Since the gap portion is bonded to the surface of the varistor body, the structure is such that the entire surface of the first conductive layer is sealed by the second conductive layer. Therefore, oxidation of the first conductive layer is prevented, ohmic contact is kept stable over a long period of time, and reliability is improved.
＜実施例＞
第３図は本発明に係るバリスタの正面断面図、
第４図は同じくその平面部分断面図である。図に
おいて、第１図及び第２図と同一の参照符号は同
一性ある構成部分を示している。この実施例で
は、円板状等の適当な形状に形成されたバリスタ
素体１の厚さ方向の両面に、オーム性接触となる
第１導電層２を、外周端全周に前記バリスタ素体
１の露出するギヤツプG1が生じるように、バリ
スタ素体１の面内に形成すると共に、この第１導
電層２の上から、その全面を覆い、周辺部がギヤ
ツプG1に達するように、第２導電層３を被着形
成した電極構造となつている。バリスタ素体１は
ZnO系である。第１導電層２は、銀を主成分と
し、これにオーム性接触化を助ける微量の金属成
分、例えばIn、Ga、Sn、Sb、Cd、Zn、Alの少
なくとも一種を添加し、これらをフリツトと共に
バリスタ素体１の表面にスクリーン印刷等の手段
によつて塗布し、かつ、焼付ける。第２導電層３
は銀ペーストをスクリーン印刷等の手段によつて
塗布焼付けする。用いられる銀ペーストは、銀を
主成分とし、フリツトを含み、更に添加物を含む
ことがある。<Example> FIG. 3 is a front sectional view of a varistor according to the present invention,
FIG. 4 is also a partial cross-sectional plan view thereof. In the figures, the same reference numerals as in FIGS. 1 and 2 indicate the same components. In this embodiment, a first conductive layer 2 for ohmic contact is applied to both sides in the thickness direction of a varistor element 1 formed in an appropriate shape such as a disk shape, and the first conductive layer 2 is applied to the entire outer circumference of the varistor element. The first conductive layer 2 is formed in the plane of the varistor body 1 so that an exposed gap G1 is formed, and the first conductive layer 2 is covered over the entire surface so that the peripheral part reaches the gap G1 . It has an electrode structure in which a second conductive layer 3 is deposited. Ballista body 1 is
It is ZnO based. The first conductive layer 2 is mainly composed of silver, to which is added a trace amount of a metal component that helps make ohmic contact, such as at least one of In, Ga, Sn, Sb, Cd, Zn, and Al, and these are fritted. At the same time, it is coated on the surface of the varistor body 1 by means such as screen printing and baked. Second conductive layer 3
The silver paste is applied and baked by means such as screen printing. The silver paste used has silver as its main component, contains frit, and may further contain additives.
第１導電層２は、製造工程での印刷位置ズレに
伴う電極面積の変動を防止するため、外周端全周
にバリスタ素体１の露出するギヤツプG1が生じ
るように、バリスタ素体１より小さい平面積とな
るように形成してある。また、第２導電層３にお
いても、同様の理由により、外周端全周に第１導
電層２の露出するギヤツプG2が生じるように、
第１導電層２より小さい平面積となるように形成
してある。 The first conductive layer 2 is formed from the varistor body 1 so that a gap G 1 is formed around the entire outer periphery of the varistor body 1 in order to prevent variations in the electrode area due to misalignment of printing positions during the manufacturing process. It is formed to have a small plane area. In addition, for the same reason, in the second conductive layer 3, a gap G 2 is formed around the entire outer circumferential edge where the first conductive layer 2 is exposed.
It is formed to have a smaller planar area than the first conductive layer 2.
上述のように、第１導電層２は、周囲にバリス
タ素体１の露出するギヤツプG1が生じるように、
バリスタ素体１の面内に焼き付けられており、第
２導電層３は、フリツトを含み、第１導電層２よ
り平面積が大きくなるように第１導電層２の表面
に付着されると共に、周辺部がギヤツプG1の部
分でバリスタ素体１の表面に接着されているか
ら、第２導電層３の周辺部がギヤツプG1に付着
する部分で、接着強度が向上する。しかも、第２
導電層３はオーム性接触電極として形成する必要
がなく、そのフリツト含有量を高め、バリスタ素
体１に対する接着強度を高めることができる。こ
のため、第２導電層３によつてバリスタ素体１に
対する第１導電層２の接着強度を補強し、バリス
タ素体１の結晶が、約100μｍ前後と一般のコン
デンサ素体の数倍〜数十倍も大きくなることのあ
るZnO系バリスタにおいて、電極剥離を防止し、
不良率を低減させ、歩留りを向上させることがで
きる。 As described above, the first conductive layer 2 is formed so that a gap G1 is formed around the varistor body 1 to expose the varistor body 1.
The second conductive layer 3 includes a frit and is attached to the surface of the first conductive layer 2 so as to have a larger planar area than the first conductive layer 2. Since the peripheral portion is bonded to the surface of the varistor body 1 at the gap G1, the adhesive strength is improved at the portion where the peripheral portion of the second conductive layer 3 adheres to the gap G1 . Moreover, the second
The conductive layer 3 does not need to be formed as an ohmic contact electrode, and its frit content can be increased and its adhesive strength to the varistor body 1 can be increased. Therefore, the adhesion strength of the first conductive layer 2 to the varistor body 1 is reinforced by the second conductive layer 3, and the crystal size of the varistor body 1 is approximately 100 μm, several times to several times that of a general capacitor body. Prevents electrode peeling in ZnO-based varistors, which can be up to 10 times larger.
It is possible to reduce the defective rate and improve yield.
第１導電層２は、バリスタ素体１の面内に焼き
付けられ、バリスタ素体１との間でオーム性接触
を構成しており、第２導電層３は第１導電層２の
表面に付着されているから、オーム性接触は第１
導電層２によつて得られ、第２導電層３はバリス
タ特性に関して直接には関与しない。しかも、第
２導電層３は、周辺部がギヤツプの部分でバリス
タ素体１の表面に接着されるのみである。このた
め、第２導電層３のフリツト含有量を増大させ、
接着強度を高めながら、バリスタ素体１の結晶が
約100μｍ前後と一般のコンデンサ素体の数倍〜
数十倍も大きくなることのあるZnO系バリスタに
おいて、フリツト拡散によるバリスタ特性の劣化
を防止できる。 The first conductive layer 2 is baked into the plane of the varistor body 1 and forms ohmic contact with the varistor body 1, and the second conductive layer 3 is attached to the surface of the first conductive layer 2. Therefore, ohmic contact is the first
The second conductive layer 3 does not directly contribute to the varistor properties. Moreover, the second conductive layer 3 is only bonded to the surface of the varistor body 1 at the peripheral portion where the gap is formed. Therefore, the frit content of the second conductive layer 3 is increased,
While increasing the adhesive strength, the crystal of the varistor element 1 is approximately 100μm, which is several times that of a general capacitor element.
In ZnO-based varistors, which can be several tens of times larger, deterioration of varistor characteristics due to flit diffusion can be prevented.
第１導電層２は、銀を主成分とし、オーム性接
触化を助ける金属成分添加物及びフリツトを含
み、バリスタ素体１の面内に焼き付けられ、バリ
スタ素体１との間でオーム性接触を構成している
から、ZnO系焼結体自身の持つバリスタ特性を充
分に発揮させることができる。 The first conductive layer 2 is mainly composed of silver, contains metal additives and frits that help establish ohmic contact, and is baked into the plane of the varistor body 1 to form ohmic contact with the varistor body 1. , the varistor properties of the ZnO-based sintered body itself can be fully exhibited.
第２導電層３は、半田付け性の良好な銀を主成
分としているから、リード線４，５を確実に、か
つ、強固に半田付けでき、しかも、第１導電層２
によるオーム性接触を損なうことがない。 Since the second conductive layer 3 is mainly composed of silver having good solderability, the lead wires 4 and 5 can be reliably and firmly soldered to the first conductive layer 3.
without damaging ohmic contact.
第１導電層２はバリスタ素体１の面内に焼き付
けられており、第２導電層３は、第１導電層２よ
り平面積が大きくなるように第１導電層２の表面
に付着されると共に、周辺部がギヤツプG1の部
分でバリスタ素体１の表面に接着されているか
ら、第１導電層２の全面を第２導電層３によつて
封止した構造となる。このため、第１導電層２の
酸化が防止され、オーム性接触が長期間に亘つて
安定に保たれ、信頼性が向上する。 The first conductive layer 2 is baked into the plane of the varistor body 1, and the second conductive layer 3 is attached to the surface of the first conductive layer 2 so that its planar area is larger than that of the first conductive layer 2. At the same time, since the peripheral portion is bonded to the surface of the varistor body 1 at the gap G1, a structure is obtained in which the entire surface of the first conductive layer 2 is sealed by the second conductive layer 3. Therefore, oxidation of the first conductive layer 2 is prevented, ohmic contact is maintained stably for a long period of time, and reliability is improved.
上記実施例では、バリスタ素体１の両面に一対
の電極を有するものを例に取つて説明したが、バ
リスタ素体１の片面または両面に複数の分割電極
を有する電極構造のもの等、他の電極構造のもの
にも同様に適用が可能である。また、バリスタ素
体１の形状も、実施例に示すものに限定されな
い。 In the above embodiment, the varistor body 1 has a pair of electrodes on both sides. It can be similarly applied to electrode structures. Further, the shape of the varistor body 1 is not limited to that shown in the embodiment.
＜発明の効果＞
以上述べたように、本発明によれば、次のよう
な効果が得られる。<Effects of the Invention> As described above, according to the present invention, the following effects can be obtained.
(a) 第１導電層は、周囲にバリスタ素体の露出す
るギヤツプが生じるように、バリスタ素体の面
内に焼き付けられており、第２導電層は、フリ
ツトを含み、第１導電層より平面積が大きくな
るように第１導電層の表面に付着されると共
に、周辺部がギヤツプの部分でバリスタ素体の
表面に接着されているから、第２導電層によつ
てバリスタ素体に対する第１導電層の接着強度
を補強し、バリスタ素体の結晶が、約100μｍ
前後と一般のコンデンサ素体の数倍〜数十倍も
大きくなることのあるZnO系バリスタにおい
て、電極剥離を防止し、不良率を低減させ、歩
留りを向上させたバリスタを提供できる。(a) The first conductive layer is baked into the plane of the varistor body so as to create a gap around the varistor body where the varistor body is exposed; Since the second conductive layer is attached to the surface of the first conductive layer so as to have a large planar area, and the peripheral portion is adhered to the surface of the varistor body at the gap portion, the second conductive layer provides a large surface area for the varistor body. 1 The adhesive strength of the conductive layer is reinforced, and the crystal of the varistor element is approximately 100 μm thick.
In ZnO-based varistors, which can be several times to several tens of times larger than a general capacitor body, it is possible to provide a varistor that prevents electrode peeling, reduces defective rates, and improves yield.
(b) 第１導電層は、バリスタ素体の面内に焼き付
けられ、バリスタ素体との間でオーム性接触を
構成しており、第２導電層は第１導電層の表面
に付着され、周辺部がギヤツプの部分でバリス
タ素体の表面に接着されているから、第２導電
層のフリツト含有量を増大させて接着強度を高
めながら、バリスタ素体の結晶が約100μｍ前
後と一般のコンデンサ素体の数倍〜数十倍も大
きくなることのあるZnO系バリスタにおいて、
フリツト拡散によるバリスタ特性の劣化を防止
できる。(b) a first conductive layer is baked into the plane of the varistor body to form ohmic contact with the varistor body; a second conductive layer is attached to the surface of the first conductive layer; Since the peripheral part is bonded to the surface of the varistor body at the gap part, the frit content of the second conductive layer is increased to increase the adhesion strength, while the crystal of the varistor body is approximately 100 μm thick, which is typical for general capacitors. In ZnO-based varistors, which can be several times to several tens of times larger than the base body,
Deterioration of varistor characteristics due to flitt diffusion can be prevented.
(c) 第１導電層は、銀を主成分とし、オーム性接
触化を助ける金属成分添加物及びフリツトを含
み、バリスタ素体の面内に焼き付けられ、バリ
スタ素体との間でオーム性接触を構成している
から、ZnO系焼結体自身の持つバリスタ特性を
充分に発揮させ得るバリスタを提供できる。(c) The first conductive layer is mainly composed of silver, contains metal component additives and frits that help establish ohmic contact, is baked into the plane of the varistor body, and makes ohmic contact with the varistor body. Therefore, it is possible to provide a varistor that can fully exhibit the varistor properties of the ZnO-based sintered body itself.
(d) 第２導電層は、半田付け性の良好な銀を主成
分としているから、リード線を確実に、かつ、
強固に半田付けでき、しかも、第１導電層によ
るオーム性接触を損なうことのないバリスタを
提供できる。(d) Since the second conductive layer is mainly composed of silver, which has good solderability, the lead wire can be connected reliably and
It is possible to provide a varistor that can be firmly soldered and does not impair the ohmic contact provided by the first conductive layer.
(e) 第１導電層はバリスタ素体の面内に焼き付け
られており、第２導電層は、第１導電層より平
面積が大きくなるように第１導電層の表面に付
着されると共に、周辺部がギヤツプの部分でバ
リスタ素体の表面に接着されているから、第１
導電層の酸化を防止し、オーム性接触を長期間
に亘つて安定に保ち得る高信頼度のバリスタを
提供できる。(e) The first conductive layer is baked into the plane of the varistor body, and the second conductive layer is attached to the surface of the first conductive layer so as to have a larger planar area than the first conductive layer, and Since the peripheral part is glued to the surface of the varistor body at the gap part, the first
It is possible to provide a highly reliable varistor that can prevent oxidation of the conductive layer and maintain stable ohmic contact for a long period of time.
第１図は従来のバリスタの正面断面図、第２図
は同じく平面断面図、第３図は本発明に係るバリ
スタの正面断面図、第４図は同じくその平面部分
断面図である。
１……バリスタ素体、２……第１導電層、３…
…第２導電層、G1……ギヤツプ。
FIG. 1 is a front sectional view of a conventional varistor, FIG. 2 is a sectional plan view thereof, FIG. 3 is a front sectional view of a varistor according to the present invention, and FIG. 4 is a partial sectional plan view thereof. 1... Varistor element body, 2... First conductive layer, 3...
...Second conductive layer, G 1 ...gap.
Claims (1)
とを含むバリスタであつて、 前記バリスタ素体は、ZnO系焼結体でなり、 前記第１導電層は、銀を主成分とし、オーム性
接触化を助ける金属成分添加物及びフリツトを含
み、周囲に前記バリスタ素体の露出するギヤツプ
が生じるように、前記バリスタ素体の面内に焼き
付けられ、前記バリスタ素体との間でオーム性接
触を構成しており、 前記第２導電層は、銀を主成分とし、フリツト
を含み、前記第１導電層より平面積が大きくなる
ように前記第１導電層の表面に付着されると共
に、周辺部が前記ギヤツプの部分で前記バリスタ
素体の表面に接着されている バリスタ。[Scope of Claims] 1. A varistor including a varistor body, a first conductive layer, and a second conductive layer, wherein the varistor body is made of a ZnO-based sintered body, and the first conductive layer is , which contains silver as a main component and includes a metal component additive and frit to help make ohmic contact, is baked into the surface of the varistor body so as to create a gap around the varistor body where the varistor body is exposed, and the varistor The second conductive layer is in ohmic contact with the element body, and the second conductive layer is mainly composed of silver and includes a frit, and the first conductive layer has a larger planar area than the first conductive layer. The varistor is attached to the surface of the varistor body, and the peripheral portion is bonded to the surface of the varistor body at the gap portion.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58242834A JPS60133701A (en) | 1983-12-21 | 1983-12-21 | Varistor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58242834A JPS60133701A (en) | 1983-12-21 | 1983-12-21 | Varistor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60133701A JPS60133701A (en) | 1985-07-16 |
| JPH0510802B2 true JPH0510802B2 (en) | 1993-02-10 |
Family
ID=17094979
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58242834A Granted JPS60133701A (en) | 1983-12-21 | 1983-12-21 | Varistor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60133701A (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56110201A (en) * | 1980-02-05 | 1981-09-01 | Nippon Denso Co | Method of forming positive temperature coefficient porcelain semiconductor |
| JPH05107201A (en) * | 1991-10-21 | 1993-04-27 | Toshiba Corp | Underwater apparatus for detecting defect |
-
1983
- 1983-12-21 JP JP58242834A patent/JPS60133701A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56110201A (en) * | 1980-02-05 | 1981-09-01 | Nippon Denso Co | Method of forming positive temperature coefficient porcelain semiconductor |
| JPH05107201A (en) * | 1991-10-21 | 1993-04-27 | Toshiba Corp | Underwater apparatus for detecting defect |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60133701A (en) | 1985-07-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4316171A (en) | Non-linear resistance elements and method for manufacturing same | |
| US5184287A (en) | Chip type solid electrolytic capacitor | |
| JPH10223409A (en) | Multilayer chip varistor and production thereof | |
| JP3777856B2 (en) | Electronic components for surface mounting | |
| JPH0510802B2 (en) | ||
| US3182118A (en) | Method of providing contacts on semiconductive ceramic bodies of n-type oxidic material and contacts produced thereby | |
| JPS60142503A (en) | Varistor | |
| GB2044531A (en) | Non-linear resistance elements and method for manufacturing same | |
| JP2967221B2 (en) | Positive thermistor element | |
| JPH0113365Y2 (en) | ||
| JPS5919364Y2 (en) | barista | |
| JP2649545B2 (en) | Electrode formation method of zinc oxide type varistor | |
| JPS63285906A (en) | Laminated ceramic varistor | |
| JPS60701A (en) | Ormic electrode | |
| JPS6343876B2 (en) | ||
| JPH0349365Y2 (en) | ||
| JPH0214162Y2 (en) | ||
| JPS6322444B2 (en) | ||
| JP3016560B2 (en) | Method for manufacturing voltage non-linear resistor | |
| JPH0113361Y2 (en) | ||
| JPS6210980Y2 (en) | ||
| JPH01289213A (en) | Manufacture of voltage-dependent nonlinear resistance element | |
| JP2560872B2 (en) | Manufacturing method of positive temperature coefficient thermistor | |
| JP2533247Y2 (en) | Varistor | |
| JP2559524Y2 (en) | Positive characteristic thermistor device |