JPH0897003A - Thick film resistor circuit and manufacture thereof - Google Patents
Thick film resistor circuit and manufacture thereofInfo
- Publication number
- JPH0897003A JPH0897003A JP6235382A JP23538294A JPH0897003A JP H0897003 A JPH0897003 A JP H0897003A JP 6235382 A JP6235382 A JP 6235382A JP 23538294 A JP23538294 A JP 23538294A JP H0897003 A JPH0897003 A JP H0897003A
- Authority
- JP
- Japan
- Prior art keywords
- thick film
- tip
- resistance
- pattern
- thick
- 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.)
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- Non-Adjustable Resistors (AREA)
- Semiconductor Integrated Circuits (AREA)
- Details Of Resistors (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、高周波信号処理回路に
搭載するに好適な厚膜抵抗回路およびその製造方法に関
する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thick film resistance circuit suitable for mounting on a high frequency signal processing circuit and a method for manufacturing the same.
【０００２】[0002]
【従来の技術】図４は、セラミックス基板上に形成され
た厚膜抵抗回路を示す平面図（ａ）およびＡ−Ａ断面図
（ｂ）である。この厚膜抵抗回路を製造するには、先
ず、Ａｌ2 Ｏ3 ，ＡｌＮ等のセラミックス基板３１上に
導体ペーストを印刷、焼成して電極５２，５２を形成す
る。次に、電極５２，５２の先端部５２ａ，５２ａに一
部が重なるように抵抗体ペーストを印刷、焼成して厚膜
抵抗５１を形成する。2. Description of the Related Art FIG. 4 is a plan view (a) and an AA sectional view (b) showing a thick film resistance circuit formed on a ceramic substrate. In order to manufacture this thick film resistance circuit, first, a conductor paste is printed and fired on a ceramic substrate 31 such as Al 2 O 3 or AlN to form electrodes 52 and 52. Next, the resistor paste is printed and baked so that the tip portions 52a and 52a of the electrodes 52 and 52 are partially overlapped, and the thick film resistor 51 is formed.
【０００３】一般に、焼成後の厚膜抵抗５１の抵抗値に
は、±２０％〜±３０％のばらつきがあるため、厚膜抵
抗５１の設計抵抗値を所望の抵抗値よりも±２０〜±３
０％低い抵抗値に設定しておき、焼成後、厚膜抵抗５１
の抵抗値を測定しながらレーザトリミング法やサンドブ
ラスト法等を用いて厚膜抵抗５１の一部をカットするこ
とによりその抵抗値を上げ、これにより所望の抵抗値の
厚膜抵抗を得る手法が用いられている。Generally, since the resistance value of the thick film resistor 51 after firing has a variation of ± 20% to ± 30%, the design resistance value of the thick film resistor 51 is ± 20 to ± more than the desired resistance value. Three
The resistance value is set to 0% lower, and after firing, the thick film resistance 51
The resistance value of the thick film resistor 51 is increased by cutting a part of the thick film resistor 51 by using a laser trimming method or a sandblast method while measuring the resistance value of the thick film resistor 51, thereby obtaining a thick film resistor having a desired resistance value. Has been.
【０００４】図５は、レーザトリミング法によりトリミ
ングされた厚膜抵抗の例を示す図である。図５（ａ）
は、Ｌ字状にカットされた厚膜抵抗、図５（ｂ）は、ダ
ブルカットされた厚膜抵抗に示している。厚膜抵抗５１
を、例えばこれらの図に示すようにカットすることによ
り、その厚膜抵抗５１の抵抗値を、所望の抵抗値の、例
えば±１％，±０．５％等のばらつきの範囲内に収め、
高精度の抵抗値を得ることができる。FIG. 5 is a diagram showing an example of a thick film resistor trimmed by a laser trimming method. FIG. 5 (a)
Shows a thick film resistor cut in an L shape, and FIG. 5B shows a double cut thick film resistor. Thick film resistor 51
By cutting as shown in these figures, the resistance value of the thick film resistor 51 is kept within a range of variation of desired resistance value, for example, ± 1%, ± 0.5%,
It is possible to obtain a highly accurate resistance value.
【０００５】一般に、厚膜技術では、導体や抵抗体を焼
成することにより、セラミックス基板上に膜として接着
させる必要があるため、導体や抵抗体には、一般に、ガ
ラス等のフリットが含有されている。特に抵抗体には、
一般に、抵抗体の要素である酸化ルテニウムにガラスが
多く含まれており、酸化ルテニウムとガラスとの混合割
合でシート抵抗（単位面積あたりの抵抗値）が調整され
る。このため、厚膜抵抗では、誘電体であるガラスによ
る誘電損失による伝送損失が生じる。特に、３ＧＨz 〜
３０ＧＨZ 程度のマイクロ波帯域の高周波信号伝送路に
ガラス成分を多く含む厚膜抵抗を用いると、誘電損失が
大きく問題がある。Generally, in the thick film technology, it is necessary to bond a conductor or resistor as a film by firing the conductor or resistor, so that the conductor or resistor generally contains frit such as glass. There is. Especially for resistors
Generally, a large amount of glass is contained in ruthenium oxide, which is an element of a resistor, and the sheet resistance (resistance value per unit area) is adjusted by the mixing ratio of ruthenium oxide and glass. Therefore, in the thick film resistor, transmission loss occurs due to dielectric loss due to glass as a dielectric. In particular, 3GH z ~
With the thick-film resistor containing a large amount of glass component to the high-frequency signal transmission line of a microwave band of about 30GH Z, there is a dielectric loss greater problem.
【０００６】この伝送損失を避けるために、マイクロ波
帯域の高周波信号伝送路には、従来、薄膜技術が用いら
れている。その理由は、薄膜の場合、厚膜と違って、導
体や抵抗体にフリットは入っておらず、また厚膜と比べ
より密な金属膜であることから、マイクロストリップラ
インやコプレーナライン等、インピーダンス制御された
比較的理論構造に近い伝送線路構造を得ることができる
からである。In order to avoid this transmission loss, thin film technology has been conventionally used for the high frequency signal transmission line in the microwave band. The reason for this is that, in the case of a thin film, unlike a thick film, there are no frit in the conductor and resistor, and because it is a denser metal film compared to a thick film, impedance such as microstrip line and coplanar line This is because it is possible to obtain a controlled transmission line structure that is relatively close to the theoretical structure.
【０００７】[0007]
【発明が解決しようとする課題】しかし、厚膜は、薄膜
と比較し、高温で焼成されているため耐熱性に優れ、許
容電力も大きく、また低コストで製造でき、組立作業も
容易であるという長所がある。このため、マイクロ波帯
域においても厚膜技術を採用することが好ましいが、マ
イクロ波帯域の高周波信号伝送路に厚膜を採用するに
は、以下のような各種の問題を解決する必要がある。However, compared with a thin film, a thick film is excellent in heat resistance because it is fired at a high temperature, has a large allowable power, can be manufactured at low cost, and is easy to assemble. There is an advantage called. Therefore, it is preferable to adopt the thick film technique even in the microwave band, but in order to adopt the thick film in the high frequency signal transmission line of the microwave band, it is necessary to solve the following various problems.
【０００８】（ａ）厚膜は、スクリーン印刷法により基
板状にペーストを印刷して形成されるため、スクリーン
の厚みやメッシュ数、ペースト粘度と抵抗値等の制限が
あり、例えば厚膜抵抗ペーストを、乾燥時に２５μｍ
厚、焼成後に１２〜１４μｍ厚の均一膜となるように印
刷して焼成後所望の抵抗値を得るには、０．３ｍｍ×
０．３ｍｍ程度の寸法が限界であり、これ以上寸法の小
さな厚膜抵抗を形成するのは困難である。(A) Since the thick film is formed by printing a paste on a substrate by a screen printing method, there are restrictions on the thickness of the screen, the number of meshes, the paste viscosity and the resistance value. 25 μm when dried
In order to obtain a desired resistance value after printing by printing so as to obtain a uniform film having a thickness of 12 to 14 μm after firing, 0.3 mm ×
The limit is about 0.3 mm, and it is difficult to form a thick film resistor having a smaller dimension than this.
【０００９】（ｂ）前述したように、厚膜抵抗は、一般
に酸化ルテニウム等の抵抗体の要素にガラスを混ぜ、そ
れらの割合でシート抵抗が調整されるが、高周波帯域に
おける誘電損失を減らすためにはできるだけガラス成分
の少ない、例えばシート抵抗が１０Ω／□等、シート抵
抗の低い抵抗体を選択した方が有利である。ところがマ
イクロ波帯域の信号を取扱う高周波回路であっても、信
号系の５０Ωや７５Ωの抵抗以外、例えば減衰器やバイ
アス回路等において数百Ω以上の抵抗が必要となる。そ
の場合にシート抵抗の異なる抵抗ペースト材料を何種類
も用いると、その抵抗ペースト材料の数だけスクリーン
が必要となり、スクリーンの数が増え、コスト高とな
る。そこで、なるべく低いシート抵抗の抵抗材料であっ
て、かつ少ない種類の材料を用いることによりスクリー
ンの数を減らし、低コストの高周波回路を形成する必要
がある。(B) As described above, in the thick film resistance, glass is generally mixed with the element of the resistor such as ruthenium oxide and the sheet resistance is adjusted by the ratio thereof, but in order to reduce the dielectric loss in the high frequency band. For this purpose, it is advantageous to select a resistor having a low glass resistance, for example, a sheet resistance of 10 Ω / □ or the like and a low sheet resistance. However, even in a high-frequency circuit that handles a signal in the microwave band, a resistance of several hundred Ω or more is required in an attenuator or a bias circuit in addition to the resistance of 50 Ω or 75 Ω in the signal system. In this case, if many kinds of resistance paste materials having different sheet resistances are used, as many screens as the resistance paste materials are required, the number of screens is increased and the cost is increased. Therefore, it is necessary to reduce the number of screens and form a high-frequency circuit at low cost by using a resistance material having a sheet resistance as low as possible and using a small number of types of materials.
【００１０】（ｃ）前述したように、焼成後の厚膜抵抗
の抵抗値は、±２０％〜±３０％のばらつきがある。そ
こで所望の抵抗値よりも２０〜３０％低い抵抗値を得る
ように設計しておき、焼成後その抵抗値を測定しなが
ら、±１％や±０．５％等の高精度の抵抗値の厚膜抵抗
を得るようトリミングされる。ところが、例えば、面積
の小さい厚膜抵抗や、電極間距離が幅よりも大きい寸法
を有する細長い抵抗体形状であって、かつ、乾燥時の膜
厚が２５ｍｍより薄くなったり、電極と抵抗体とのオー
バーラップ部の面積が抵抗体の面積の２０〜３０％を越
えたり、あるいは、抵抗印刷時にオーバーラップ部の距
離が０．２ｍｍ程度であっても幅が０．３ｍｍよりも狭
くなった場合等に、オーバラップ部の抵抗体が、その下
に形成されている電極用導体膜の影響で、例えば０．２
ｍｍ×０．３ｍｍよりも小さく、かつ薄く印刷されてし
まうことがある。(C) As described above, the resistance value of the thick film resistance after firing has a variation of ± 20% to ± 30%. Therefore, it is designed to obtain a resistance value 20 to 30% lower than the desired resistance value, and while measuring the resistance value after firing, it is possible to obtain a highly accurate resistance value such as ± 1% or ± 0.5%. Trimmed to obtain thick film resistance. However, for example, a thick film resistor having a small area or an elongated resistor shape having a distance between electrodes larger than the width and a film thickness when dried is less than 25 mm, or the electrode and the resistor are separated from each other. When the area of the overlapping part exceeds 20 to 30% of the area of the resistor, or the width of the overlapping part is narrower than 0.3 mm even if the distance of the overlapping part is about 0.2 mm during resistance printing. In addition, due to the influence of the electrode conductor film formed below the resistor in the overlapping portion,
It may be smaller than mm × 0.3 mm and may be printed thinly.
【００１１】図６は、抵抗体印刷時の抵抗体形状を示し
た図である。図６（ａ），図６（ｂ）はそれぞれ断面形
状，平面形状を示し、オーバーラップ部が、破線のよう
な設計値どおりの厚さ、面積に印刷されないことがあ
る。その場合、焼成後の抵抗値が設計値よりも高くなっ
てしまい、さらに所望の抵抗値よりも高くなってしまう
事態が発生する場合がある。所望の抵抗値よりも高くな
ってしまった厚膜抵抗はトリミングにより抵抗値を下げ
ることはできず、基板全体を廃棄することになる。FIG. 6 is a diagram showing the shape of the resistor when printing the resistor. 6A and 6B show a cross-sectional shape and a planar shape, respectively, and the overlapping portion may not be printed in the thickness and area as designed such as the broken line. In that case, the resistance value after firing may be higher than the design value, and may be higher than the desired resistance value. The thick film resistor, which has become higher than the desired resistance value, cannot be lowered in resistance by trimming, and the entire substrate is discarded.
【００１２】図７は、厚膜抵抗の膜厚が不均一に印刷さ
れた状態を示す図である。図７に示す厚膜抵抗７３は、
電極パターン５２どうしの間の寸法Ｌが厚膜抵抗７３の
幅よりも狭い場合の例であり、厚膜抵抗７３が均一な厚
さに印刷されず、その中央部が盛り上がった形状に印刷
されている。本発明は、上記事情に鑑み、小面積であっ
てもその抵抗値のばらつきを押さえた厚膜抵抗回路の製
造方法およびその製造方法により製造された厚膜抵抗回
路を提供することを第１の目的とする。FIG. 7 is a diagram showing a state in which the film thickness of the thick film resistor is printed unevenly. The thick film resistor 73 shown in FIG.
This is an example in which the dimension L between the electrode patterns 52 is narrower than the width of the thick film resistor 73. The thick film resistor 73 is not printed to have a uniform thickness, but its central portion is printed in a raised shape. There is. In view of the above circumstances, the present invention provides a method for manufacturing a thick film resistance circuit that suppresses variations in resistance even if the area is small, and a thick film resistance circuit manufactured by the manufacturing method. To aim.
【００１３】また、本発明は、焼成後の抵抗値が所望値
よりも高い抵抗値を有していても、その抵抗値を調整す
ることのできる厚膜抵抗回路の製造方法、およびその製
造方法により製造された厚膜抵抗回路を提供することを
第２の目的とする。The present invention also provides a method of manufacturing a thick film resistance circuit capable of adjusting the resistance value after firing, even if the resistance value is higher than a desired value, and a method of manufacturing the same. A second object is to provide a thick film resistance circuit manufactured by
【００１４】[0014]
【課題を解決するための手段】上記第１の目的を達成す
る、本発明の厚膜抵抗回路の第１の製造方法は、先端の
一部に先端方向に突出した尖頭部を有する厚膜電極パタ
ーンを基板上に印刷して焼成し、その厚膜電極パターン
の先端部に一部が重なる厚膜抵抗パターンを印刷して焼
成し、その厚膜電極パターンを、必要に応じてトリミン
グすることを特徴とする。According to a first method of manufacturing a thick film resistance circuit of the present invention which achieves the above first object, a thick film having a pointed portion projecting in a tip direction at a part of its tip is provided. Printing an electrode pattern on a substrate and baking, printing a thick film resistance pattern that partially overlaps the tip of the thick film electrode pattern and baking, and trimming the thick film electrode pattern as necessary. Is characterized by.
【００１５】上記第１の製造方法により製造された本発
明の第１の厚膜抵抗回路は、先端の一部に先端方向に突
出した尖頭部を有する厚膜電極と、その厚膜電極の先端
部に一部が重なる厚膜抵抗体とを備えたことを特徴とす
る。また、上記第２の目的を達成する、本発明の厚膜抵
抗回路の第２の製造方法は、第１の厚膜電極パターンを
基板上に印刷して焼成し、その第１の厚膜電極パターン
の先端部に一部が重なる厚膜抵抗パターンを印刷して焼
成し、その厚膜抵抗パターンが所望の抵抗値を越える抵
抗値を有するものである場合に、その厚膜抵抗パターン
の、上記第１の厚膜電極パターンの先端部と重なった部
分を覆うとともにその先端部を越えて厚膜抵抗パターン
上に広がるように第２の厚膜電極パターンを印刷して焼
成し、その厚膜抵抗パターンを、必要に応じてトリミン
グすることを特徴とする。The first thick film resistance circuit of the present invention manufactured by the above-mentioned first manufacturing method has a thick film electrode having a pointed tip projecting toward the tip in a part of the tip, and the thick film electrode of the thick film electrode. A thick film resistor part of which overlaps at the tip is provided. A second method of manufacturing a thick film resistance circuit according to the present invention, which achieves the second object, comprises printing a first thick film electrode pattern on a substrate and firing the first thick film electrode. When a thick film resistance pattern that partially overlaps the tip of the pattern is printed and fired, and the thick film resistance pattern has a resistance value exceeding a desired resistance value, the thick film resistance pattern The second thick film electrode pattern is printed and baked so as to cover the portion of the first thick film electrode pattern that overlaps with the tip portion and spread over the thick film resistor pattern beyond the tip portion, and then the thick film resistor pattern is baked. The feature is that the pattern is trimmed as needed.
【００１６】この第２の製造方法において、上記第２の
厚膜電極パターンを形成する際、もしくは、上記第１の
厚膜電極パターンを形成する際および上記第２の厚膜電
極を形成する際の双方において、先端の一部に先端方向
に突出した尖頭部を有する厚膜電極パターンを形成する
ことが好ましい。上記第２の製造方法により製造された
本発明の第２の厚膜抵抗回路は、第１の厚膜電極と、そ
の第１の厚膜電極の先端部に一部が重なる厚膜抵抗体
と、その厚膜抵抗体の上記第１の厚膜電極の先端部と重
なった部分を覆うとともにその先端部を越えて厚膜抵抗
体上に広がる第２の厚膜電極を備えたことを特徴とす
る。In the second manufacturing method, when the second thick film electrode pattern is formed, or when the first thick film electrode pattern is formed and when the second thick film electrode is formed. In both cases, it is preferable to form a thick film electrode pattern having a pointed portion protruding in the tip direction at a part of the tip. A second thick film resistance circuit of the present invention manufactured by the second manufacturing method described above includes a first thick film electrode and a thick film resistor partially overlapping the tip portion of the first thick film electrode. And a second thick film electrode that covers a portion of the thick film resistor that overlaps with the tip portion of the first thick film electrode and that extends over the thick film resistor beyond the tip portion. To do.
【００１７】この第２の厚膜抵抗回路において、上記第
２の厚膜電極、もしくは、上記第２の厚膜電極に加えて
さらに上記第１の厚膜電極が、その電極の先端の一部に
先端方向に突出した尖頭部を有するものであってもよ
い。In the second thick film resistance circuit, the second thick film electrode, or the first thick film electrode in addition to the second thick film electrode is part of the tip of the electrode. It may have a pointed portion protruding in the distal direction.
【００１８】[0018]
【作用】本発明の上記第１の製造方法によれば、電極に
尖頭部が形成されているため、小さい形状の厚膜抵抗で
あっても、電極上のオーバラップ部を所期の形状、所期
の厚さに印刷することができ、形状や厚さの再現性のよ
い抵抗パターンが得られ、抵抗値のばらつきの少ない厚
膜抵抗が形成される。According to the first manufacturing method of the present invention, since the electrode is provided with the pointed portion, even if the thick film resistor has a small shape, the overlapped portion on the electrode has a desired shape. In addition, it is possible to print to a desired thickness, obtain a resistance pattern with good reproducibility of shape and thickness, and form a thick film resistance with less variation in resistance value.
【００１９】また本発明の第２の製造方法によれば、焼
成後所望の抵抗値よりも大きな抵抗値の厚膜抵抗が得ら
れてしまった場合に上記第２の厚膜電極パターンを印刷
して焼成するものであり、これにより所望の抵抗値と同
一もしくはそれよりも低い抵抗値の厚膜抵抗が得られ、
必要に応じてトリミングを行なうことにより、抵抗値が
高精度に調整された厚膜抵抗を得ることができる。According to the second manufacturing method of the present invention, the second thick film electrode pattern is printed when a thick film resistance having a resistance value larger than a desired resistance value is obtained after firing. It is to be fired by this, thereby obtaining a thick film resistor having a resistance value equal to or lower than a desired resistance value,
By performing trimming as necessary, a thick film resistor whose resistance value is adjusted with high precision can be obtained.
【００２０】また、上記第２の製造方法において、上記
第２の厚膜電極パターンを形成する際、もしくは、上記
第１の厚膜電極パターンを形成する際および上記第２の
厚膜電極を形成する際の双方において、先端の一部に先
端方向に突出した尖頭部を有する厚膜電極パターンを形
成した場合、トリミング前の厚膜抵抗のばらつきが押さ
えられる。In the second manufacturing method, when the second thick film electrode pattern is formed, or when the first thick film electrode pattern is formed and the second thick film electrode is formed. In both cases, when a thick film electrode pattern having a pointed portion protruding in the tip direction is formed on a part of the tip, variation in the thick film resistance before trimming is suppressed.
【００２１】さらに、上記第１の製造方法及び／又は上
記第２の製造方法により製造された厚膜抵抗回路は、焼
成後の抵抗値のばらつきが押さえられているためその後
の調整が容易であるため、あるいは所望値を越える抵抗
値の厚膜抵抗が得られても廃棄することなく調整が可能
であるため、コストの安い厚膜抵抗回路が得られる。ま
た小面積であっても高精度の抵抗値をもった厚膜抵抗が
形成され、マイクロ波帯域の信号伝送用として好適であ
る。Further, in the thick film resistance circuit manufactured by the first manufacturing method and / or the second manufacturing method, the variation in the resistance value after firing is suppressed, and hence the subsequent adjustment is easy. Therefore, or even if a thick film resistor having a resistance value exceeding the desired value is obtained, adjustment can be performed without discarding, and thus a thick film resistor circuit with low cost can be obtained. Further, a thick film resistor having a highly accurate resistance value is formed even in a small area, which is suitable for signal transmission in the microwave band.
【００２２】[0022]
【実施例】以下、本発明の実施例について説明する。図
１は、本発明の第１の製造方法を適用して製造された厚
膜抵抗回路の各種例を示す図、図２は、電極どうしの距
離（抵抗体の長さＬ）が抵抗体の幅よりも短かい場合の
断面形状を示した図である。Embodiments of the present invention will be described below. FIG. 1 is a view showing various examples of a thick film resistance circuit manufactured by applying the first manufacturing method of the present invention, and FIG. 2 shows that the distance between electrodes (length L of the resistor) is the resistance. It is the figure which showed the cross-sectional shape at the time of being shorter than width.
【００２３】図１（ａ）に示す実施例には、電極１１の
先端部１１ａの中央に、先端方向に突出した尖頭部１１
ｂが形成されている。また図１（ｂ）に示す実施例に
は、電極１３の先端部１３ａの両端に、先端方向に突出
した尖頭部１３ｂが形成されている。さらに、図１
（ｃ），（ｄ）に示す各実施例には、それぞれ図１
（ａ），（ｂ）に示す実施例と同様な形状の電極１１，
１１；１３，１３に加え、それらの電極の１１，１１；
１３，１３どうしの中間に中間電極２１，２３が形成さ
れている。In the embodiment shown in FIG. 1 (a), a tip 11 protruding toward the tip is provided at the center of the tip 11a of the electrode 11.
b is formed. Further, in the embodiment shown in FIG. 1B, the tips 13a of the electrode 13 are formed at both ends with pointed portions 13b protruding in the tip direction. Furthermore, FIG.
In each of the embodiments shown in (c) and (d), FIG.
An electrode 11 having a shape similar to that of the embodiment shown in (a) and (b),
11; 13, 13, in addition to those electrodes 11, 11;
Intermediate electrodes 21 and 23 are formed between 13 and 13.
【００２４】これらの各種形状のうち、幅Ｗが０．５ｍ
ｍ以下の抵抗であって、幅Ｗよりも長さＬが長い場合は
図１（ａ）の形状、幅Ｗよりも長さＬが短い場合は図１
（ｂ）の形状が望ましい。幅Ｗよりも長さＬが短い場
合、図１（ｂ）に示す形状の電極１３，１３を形成する
と、図２に示すように厚さの均一な厚膜抵抗１２を得る
ことができる（従来の場合の、図７参照） 図１（ａ）に示す電極パターンの場合、電流の流れは、
尖頭部１１ｂどうしを結ぶ、厚膜抵抗１２の中央に集中
するため、レーザトリミング等によりトリミングを行な
う際は、図５（ａ）に示すようなＬ字状のカットが好ま
しい。一方、図１（ｂ）に示す電極パターンの場合、電
流の流れは、尖頭部１３ｂどうしを結ぶ、厚膜抵抗１２
の両端に集中するため、レーザトリミング等によりトリ
ミングを行なう際は、図５（ｂ）に示すようなダブルカ
ット、もしくは、その切断線が一本だけのシングルカッ
トにより抵抗値の粗調整を行ない、厚膜抵抗の中心を、
電極１３どうしを結ぶ方向にカットすることにより微調
整を行なうことができる。Of these various shapes, the width W is 0.5 m
When the resistance is m or less and the length L is longer than the width W, the shape shown in FIG. 1A is obtained. When the length L is shorter than the width W, the shape shown in FIG.
The shape of (b) is desirable. When the length L is shorter than the width W and the electrodes 13 and 13 having the shape shown in FIG. 1B are formed, a thick film resistor 12 having a uniform thickness can be obtained as shown in FIG. In the case of, refer to FIG. 7) In the case of the electrode pattern shown in FIG.
Since it concentrates on the center of the thick film resistor 12 connecting the pointed portions 11b, it is preferable to make an L-shaped cut as shown in FIG. 5A when performing trimming by laser trimming or the like. On the other hand, in the case of the electrode pattern shown in FIG. 1B, the current flow is such that the thick film resistor 12 connecting the pointed portions 13b is connected.
Since it concentrates on both ends of the resistance value, when trimming is performed by laser trimming or the like, the resistance value is roughly adjusted by a double cut as shown in FIG. 5B or a single cut having only one cutting line. The center of thick film resistance
Fine adjustment can be performed by cutting in the direction in which the electrodes 13 are connected.
【００２５】図１（ｃ），（ｄ）の中間電極２１，２３
は、例えば、厚膜抵抗の幅Ｗが０．２ｍｍ以下であって
長さＬが長い場合に、印刷時に抵抗パターンが断線パタ
ーンとして印刷されやすく、これを防ぐ目的や、トリミ
ング時に測定用のプローブをあて、中間電極２１，２３
の左右に分けて粗調整と微調整を行なう目的で形成され
る。Intermediate electrodes 21, 23 shown in FIGS. 1 (c) and 1 (d)
For example, when the width W of the thick film resistor is 0.2 mm or less and the length L is long, the resistance pattern is likely to be printed as a disconnection pattern at the time of printing. The intermediate electrodes 21, 23
It is formed for the purpose of performing the rough adjustment and the fine adjustment separately for the left and right sides.
【００２６】尚、図１に示す例は、電極１１，１３の先
端１１ａ，１３ａの中央ないし両端に１つもしくは２つ
の尖頭部１１ｂ，１３ｂを有する例であるが、尖頭部は
中央ないし両端に限られるものではなく、またその数も
１つもしくは２つに限れるものでもなく、電極の先端部
が複雑に凹凸を繰り返すものであってもよい。図３は、
本発明の第２の製造方法により製造された厚膜抵抗回路
の例を示す図である。In the example shown in FIG. 1, the tips 11a, 13a of the electrodes 11, 13 have one or two cusps 11b, 13b at the center or both ends thereof. It is not limited to the both ends, and the number thereof is not limited to one or two, and the tip portion of the electrode may have complicated irregularities. Figure 3
It is a figure which shows the example of the thick film resistance circuit manufactured by the 2nd manufacturing method of this invention.
【００２７】先ず、図３（ａ）に示すように、第１の電
極１１，１１を印刷、焼成した後、第１の電極１１，１
１の先端部１１ａ，１１ａに一部が重なるように厚膜抵
抗１２が印刷、焼成される。第１の電極１１，１１の先
端部１１ａ，１１ａの中央には尖頭部１１ｂ，１１ｂが
形成されている。厚膜抵抗１２を焼成した後、厚膜抵抗
１２の抵抗値が測定される。その抵抗値が所望の抵抗値
よりも低い場合はその厚膜抵抗１２がトリミングされる
が、以下ではその抵抗値が所望の抵抗値より高かった場
合について説明する。First, as shown in FIG. 3A, the first electrodes 11, 11 are printed and fired, and then the first electrodes 11, 1 are printed.
The thick film resistor 12 is printed and fired so that a part of the thick film resistor 12 overlaps the tip portions 11a and 11a. Tip portions 11b and 11b are formed at the centers of the tip portions 11a and 11a of the first electrodes 11 and 11, respectively. After firing the thick film resistor 12, the resistance value of the thick film resistor 12 is measured. When the resistance value is lower than the desired resistance value, the thick film resistor 12 is trimmed, but the case where the resistance value is higher than the desired resistance value will be described below.
【００２８】一般に、シート抵抗の低い厚膜抵抗は、２
度以上焼成したり、焼成プロファイルが通常の焼成プロ
ファイル（例えばピーク８５０℃１０分間、１時間焼
成）よりもピーク温度が高かったりピーク温度に保持さ
れている時間が長いと、通常時よりも抵抗値が高めに出
る傾向にある。シート抵抗の高い厚膜抵抗の場合は、逆
に、抵抗値が低めに出る傾向にある。そこで、種々のシ
ート抵抗や種々の寸法の厚膜抵抗について、かつ、それ
ら種々の厚膜抵抗と種々の電極（導体）との組合せにつ
いて２度以上の焼成を行ない、その抵抗値がどのように
変化するかを測定しておく。Generally, a thick film resistor having a low sheet resistance is 2
If the firing temperature is higher than the normal firing profile or the firing profile has a higher peak temperature than the normal firing profile (for example, a firing time of 850 ° C. for 10 minutes and 1 hour), and the holding time at the peak temperature is longer, the resistance value is higher than that of the normal time. Tend to be higher. On the contrary, in the case of a thick film resistor having a high sheet resistance, the resistance value tends to be low. Therefore, various sheet resistances and thick film resistances of various sizes, and combinations of these various thick film resistances and various electrodes (conductors) were fired twice or more, and the resistance values were determined. Measure if it changes.
【００２９】そうしておいて、図３（ａ）に示すような
形状に通常どおり印刷、焼成して抵抗値を測定したとき
に所望の抵抗値より高くでた場合、次に図３（ｂ）に示
す第２の電極４１，４１を、図３（ｃ）に示すように、
厚膜抵抗１２の、第１の電極１１，１１の先端部１１
ａ，１１ａと重なったオーバーラップ部を覆うとともに
その先端部１１ａ，１１ａを越えて厚膜抵抗１２上に広
がるように形成する。この第２の電極４１，４１にも尖
頭部４１ｂ，４１ｂが形成されている。第２の電極４
１，４１は、第１の電極１１，１１の先端部１１ａ，１
１ａを越えて厚膜抵抗１２上に広がっているため、第２
の電極４１，４１の尖頭部４１ｂ，４１ｂどうしの間隔
Ｌ2 は、第１の電極１１，１１の尖頭部１１ｂ，１１ｂ
どうしの間隔Ｌよりも狭くなっている。このように、こ
の第２の電極４１，４１を形成し、厚膜抵抗１２の抵抗
値を下げる。第２の電極４１，４１の尖頭部４１ｂ，４
１ｂどうしの間隔Ｌ2 は、２度焼成時の厚膜抵抗１２の
抵抗値の変化を考慮し、２度焼成後の厚膜抵抗１２の抵
抗値が所望の抵抗値もしくはそれ以下の抵抗値となるよ
うに設定される。このようにして第２の電極４１，４１
を形成して厚膜抵抗１２の抵抗値を下げておいて、トリ
ミングによりその抵抗値を調整する。こうすることによ
り、一旦所望の抵抗値よりも高い抵抗値となってしまっ
た厚膜抵抗を、所望の抵抗値を有する厚膜抵抗として再
生することができる。If the resistance value is higher than the desired resistance value when the resistance value is measured by printing and firing as usual in the shape as shown in FIG. ) As shown in FIG. 3C, the second electrodes 41, 41 shown in FIG.
The tip portion 11 of the first electrode 11, 11 of the thick film resistor 12
It is formed so as to cover the overlapping portion overlapping with a and 11a and to spread over the thick film resistor 12 beyond the tip portions 11a and 11a thereof. The second electrodes 41, 41 are also formed with pointed portions 41b, 41b. Second electrode 4
1, 41 are the tip portions 11a, 1 of the first electrodes 11, 11.
Since it spreads over the thick film resistor 12 beyond 1a, the second
The distance L 2 between the tip portions 41b, 41b of the electrodes 41, 41 of the first electrode 11 is equal to the tip portion 11b, 11b of the first electrode 11, 11.
It is narrower than the distance L between them. Thus, the second electrodes 41, 41 are formed, and the resistance value of the thick film resistor 12 is lowered. Tip portions 41b, 4 of the second electrodes 41, 41
The distance L 2 between the 1b and the 2b is set to a desired resistance value or a resistance value less than or equal to the desired resistance value of the thick film resistor 12 in consideration of the change in the resistance value of the thick film resistor 12 during the second baking. Is set. In this way, the second electrodes 41, 41
Is formed to reduce the resistance value of the thick film resistor 12, and the resistance value is adjusted by trimming. By doing so, it is possible to regenerate a thick film resistance having a resistance value higher than a desired resistance value as a thick film resistance having a desired resistance value.
【００３０】尚、図３に示す例では、第１の電極１１，
１１および第２の電極４１，４１の双方に尖頭部１１
ｂ，１１ｂ；４１ｂ，４１ｂが形成されているが、尖頭
部は、抵抗値をトリミングにより合わせ込む必要のある
第２の電極４１，４１のみに形成してもよい。または、
抵抗値のばらつきは大きくはなるがトリミングにより調
整できる場合は第１の電極、第２の電極とも尖頭部を形
成しなくてもよい。In the example shown in FIG. 3, the first electrode 11,
11 and the second electrodes 41, 41 both have a pointed portion 11
b, 11b; 41b, 41b are formed, but the pointed portion may be formed only on the second electrodes 41, 41 whose resistance values need to be adjusted by trimming. Or
If the variation of the resistance value increases, but it can be adjusted by trimming, neither the first electrode nor the second electrode may have a pointed portion.
【００３１】以下の３つのパターンについて厚膜抵抗回
路の製造実験を行なった。シート抵抗ρはいずれもρ＝
１０Ω／□の材料を用いた。 （１）設計時 （ａ）抵抗Ｒ1 寸法：幅Ｗ×長さＬ＝０．２ｍｍ×１．０ｍｍ 設計抵抗値Ｒ1 ＝ρ・Ｌ／Ｗ＝１０×１．０／０．２＝
５０Ω 目標抵抗値 ５０Ω ±５％ （ｂ）抵抗Ｒ2 寸法：幅Ｗ×長さＬ＝０．１ｍｍ×０．８ｍｍ 設計抵抗値Ｒ2 ＝ρ・Ｌ／Ｗ＝１０×０．８／０．１＝
８０Ω 目標抵抗値 １００Ω ±５％ （ｃ）抵抗Ｒ3 寸法：幅Ｗ×長さＬ＝０．２ｍｍ×４．０ｍｍ 設計抵抗値Ｒ3 ＝ρ・Ｌ／Ｗ＝１０×４．０／０．２＝
２００Ω 目標抵抗値 ２５０Ω ±１％ （２）印刷、焼成後の実測抵抗値 （ａ）Ｒ1 ：５２Ω （ｂ）Ｒ2 ：８１Ω （ｃ）Ｒ3 ：２０５Ω （３）第２の電極４１，４１を形成（図３参照） （ａ）Ｌ2 ＝０．６０ｍｍ （ｂ）Ｌ2 ＝０．６４ｍｍ （ｃ）Ｌ2 ＝３．２０ｍｍ （４）２回目焼成後の実測抵抗値 （ａ）Ｒ1 ：３９Ω （ｂ）Ｒ2 ：８２Ω （ｃ）Ｒ3 ：１９６Ω （５）トリミング後の実測抵抗値 （ａ）Ｒ1 ：４９Ω （ｂ）Ｒ2 ：１０１Ω （ｃ）Ｒ3 ：２５０Ω となった。以上のように、１回目の焼成後に目標抵抗値
よりも高い抵抗値を得ても（上記（１）（ａ），（２）
（ａ）参照）、第２の電極を形成することにより抵抗値
を下げ、トリミングを行なうことにより目標抵抗値の厚
膜抵抗を得ることができる。A manufacturing experiment of a thick film resistance circuit was conducted for the following three patterns. Sheet resistance ρ is ρ =
A material of 10Ω / □ was used. (1) At the time of design (a) Resistance R 1 dimension: width W × length L = 0.2 mm × 1.0 mm Design resistance value R 1 = ρ · L / W = 10 × 1.0 / 0.2 =
50Ω Target resistance value 50Ω ± 5% (b) Resistance R 2 dimension: width W × length L = 0.1 mm × 0.8 mm Design resistance value R 2 = ρ · L / W = 10 × 0.8 / 0. 1 =
80Ω Target resistance value 100Ω ± 5% (c) Resistance R 3 dimensions: width W × length L = 0.2 mm × 4.0 mm Design resistance value R 3 = ρ · L / W = 10 × 4.0 / 0.0. 2 =
200Ω Target resistance value 250Ω ± 1% (2) Measured resistance value after printing and firing (a) R 1 : 52Ω (b) R 2 : 81Ω (c) R 3 : 205Ω (3) Second electrode 41, 41 (See FIG. 3) (a) L 2 = 0.60 mm (b) L 2 = 0.64 mm (c) L 2 = 3.20 mm (4) Measured resistance value after second firing (a) R 1 : 39 Ω (b) R 2 : 82 Ω (c) R 3 : 196 Ω (5) Measured resistance value after trimming (a) R 1 : 49 Ω (b) R 2 : 101 Ω (c) R 3 : 250 Ω. As described above, even if a resistance value higher than the target resistance value is obtained after the first firing (the above (1) (a), (2)).
(See (a)), the resistance value is reduced by forming the second electrode, and the thick film resistance having the target resistance value can be obtained by trimming.
【００３２】[0032]
【発明の効果】以上説明したように、本発明によれば、
小面積であっても焼成後の抵抗値のばらつきを押さえた
厚膜抵抗が形成され、また、焼成後の抵抗値が所望の抵
抗値よりも高くてもその抵抗値を低め、トリミングによ
り高精度の厚膜抵抗を得ることができる。As described above, according to the present invention,
A thick film resistor that suppresses variations in resistance value after firing is formed even with a small area, and even if the resistance value after firing is higher than the desired resistance value, the resistance value is lowered and highly accurate by trimming. The thick film resistance can be obtained.
【図１】本発明の第１の製造方法により製造された厚膜
抵抗回路の各種例を示す図である。FIG. 1 is a diagram showing various examples of a thick film resistance circuit manufactured by a first manufacturing method of the present invention.
【図２】電極どうしの距離（抵抗体の長さ）が抵抗体の
幅よりも短かい場合の断面形状を示した図である。FIG. 2 is a diagram showing a cross-sectional shape when a distance between electrodes (length of a resistor) is shorter than a width of the resistor.
【図３】本発明の第２製造方法により製造された厚膜抵
抗回路の例を示す図である。FIG. 3 is a diagram showing an example of a thick film resistance circuit manufactured by a second manufacturing method of the present invention.
【図４】セラミックス基板上に形成された厚膜抵抗回路
を示す平面図（ａ）およびＡ−Ａ断面図（ｂ）である。FIG. 4 is a plan view (a) and an AA cross-sectional view (b) showing a thick film resistance circuit formed on a ceramic substrate.
【図５】レーザトリミング法によりトリミングされた厚
膜抵抗の例を示す図である。FIG. 5 is a diagram showing an example of a thick film resistor trimmed by a laser trimming method.
【図６】抵抗体印刷時の抵抗体形状を示した図である。FIG. 6 is a diagram showing a resistor shape during resistor printing.
【図７】厚膜抵抗の膜厚が不均一に印刷された状態を示
す図である。FIG. 7 is a diagram showing a state in which the film thickness of the thick film resistor is printed unevenly.
１１，１３ 電極 １１ａ，１３ａ 電極の先端部 １１ｂ，１３ｂ 電極の尖頭部 １２，２２ 厚膜抵抗 ２１，２３ 中間電極 ４１ 第２の電極 ４１ｂ 尖頭部 11, 13 Electrodes 11a, 13a Electrode tip 11b, 13b Electrode tip 12,22 Thick film resistance 21,23 Intermediate electrode 41 Second electrode 41b Tip
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.6 識別記号 庁内整理番号 ＦＩ 技術表示箇所 Ｈ０１Ｌ 27/01 ３２１ 27/04 21/822 ─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. 6 Identification number Office reference number FI technical display location H01L 27/01 321 27/04 21/822
Claims (6)
を有する厚膜電極と、該厚膜電極の先端部に一部が重な
る厚膜抵抗体とを備えたことを特徴とする厚膜抵抗回
路。1. A thick film electrode having a pointed tip protruding in a tip direction at a part of the tip, and a thick film resistor partially overlapping the tip part of the thick film electrode. Thick film resistor circuit.
先端部に一部が重なる厚膜抵抗体と、該厚膜抵抗体の前
記第１の厚膜電極の先端部と重なった部分を覆うととも
に該先端部を越えて該厚膜抵抗体上に広がる第２の厚膜
電極を備えたことを特徴とする厚膜抵抗回路。2. A first thick film electrode, a thick film resistor that partially overlaps a tip of the first thick film electrode, and a tip of the first thick film electrode of the thick film resistor. A thick film resistance circuit comprising: a second thick film electrode that covers the overlapping portion and extends over the thick film resistor beyond the tip portion.
厚膜電極に加えてさらに前記第１の厚膜電極が、該電極
の先端の一部に先端方向に突出した尖頭部を有するもの
であることを特徴とする請求項２記載の厚膜抵抗回路。3. A second thick-film electrode, or a tip portion in which the first thick-film electrode in addition to the second thick-film electrode further protrudes in a tip direction in a part of the tip of the electrode. The thick film resistance circuit according to claim 2, wherein the thick film resistance circuit comprises:
を有する厚膜電極パターンを基板上に印刷して焼成し、 該厚膜電極パターンの先端部に一部が重なる厚膜抵抗パ
ターンを印刷して焼成し、 該厚膜抵抗パターンを、必要に応じてトリミングするこ
とを特徴とする厚膜抵抗回路の製造方法。4. A thick film resistor in which a thick film electrode pattern having a pointed portion projecting toward the tip end is printed on a substrate and baked, and a part of the thick film electrode pattern overlaps the tip end of the thick film electrode pattern. A method for producing a thick film resistance circuit, which comprises printing a pattern, firing it, and trimming the thick film resistance pattern as necessary.
して焼成し、 該第１の厚膜電極パターンの先端部に一部が重なる厚膜
抵抗パターンを印刷して焼成し、 該厚膜抵抗パターンが所望の抵抗値を越える抵抗値を有
するものである場合に、該厚膜抵抗パターンの、前記第
１の厚膜電極パターンの先端部と重なった部分を覆うと
ともに該先端部を越えて該厚膜抵抗パターン上に広がる
ように第２の厚膜電極パターンを印刷して焼成し、 該厚膜抵抗パターンを、必要に応じてトリミングするこ
とを特徴とする厚膜回路の製造方法。5. A first thick-film electrode pattern is printed on a substrate and baked, and a thick-film resistance pattern partially overlapping the tip of the first thick-film electrode pattern is printed and baked. When the thick film resistance pattern has a resistance value exceeding a desired resistance value, the thick film resistance pattern is covered with a portion overlapping the tip portion of the first thick film electrode pattern and the tip portion is A method of manufacturing a thick film circuit, characterized in that a second thick film electrode pattern is printed and baked so as to extend over the thick film resistance pattern, and the thick film resistance pattern is trimmed as necessary. .
際、もしくは前記第１の厚膜電極パターンを形成する際
および前記第２の厚膜電極を形成する際の双方におい
て、先端の一部に先端方向に突出した尖頭部を有する厚
膜電極パターンを形成することを特徴とする請求項５記
載の厚膜回路の製造方法。6. The tip of the tip is formed both when the second thick film electrode pattern is formed, or when the first thick film electrode pattern is formed and when the second thick film electrode is formed. The method for manufacturing a thick film circuit according to claim 5, wherein a thick film electrode pattern having a pointed portion protruding in a tip direction is formed on the portion.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6235382A JPH0897003A (en) | 1994-09-29 | 1994-09-29 | Thick film resistor circuit and manufacture thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6235382A JPH0897003A (en) | 1994-09-29 | 1994-09-29 | Thick film resistor circuit and manufacture thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0897003A true JPH0897003A (en) | 1996-04-12 |
Family
ID=16985259
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6235382A Withdrawn JPH0897003A (en) | 1994-09-29 | 1994-09-29 | Thick film resistor circuit and manufacture thereof |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0897003A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012186200A (en) * | 2011-03-03 | 2012-09-27 | Koa Corp | Method of manufacturing resistor |
| WO2016047259A1 (en) * | 2014-09-25 | 2016-03-31 | Koa株式会社 | Chip resistor and method for producing same |
| JP2016066743A (en) * | 2014-09-25 | 2016-04-28 | Koa株式会社 | Chip resistor |
| JP2016072298A (en) * | 2014-09-26 | 2016-05-09 | Koa株式会社 | Manufacturing method of chip resistor |
-
1994
- 1994-09-29 JP JP6235382A patent/JPH0897003A/en not_active Withdrawn
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012186200A (en) * | 2011-03-03 | 2012-09-27 | Koa Corp | Method of manufacturing resistor |
| WO2016047259A1 (en) * | 2014-09-25 | 2016-03-31 | Koa株式会社 | Chip resistor and method for producing same |
| JP2016066743A (en) * | 2014-09-25 | 2016-04-28 | Koa株式会社 | Chip resistor |
| CN106688053A (en) * | 2014-09-25 | 2017-05-17 | 兴亚株式会社 | Chip resistor and method for producing same |
| US10109398B2 (en) | 2014-09-25 | 2018-10-23 | Koa Corporation | Chip resistor and method for producing same |
| JP2016072298A (en) * | 2014-09-26 | 2016-05-09 | Koa株式会社 | Manufacturing method of chip resistor |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A300 | Withdrawal of application because of no request for examination |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 20020115 |