JP2738603B2 - Circuit board - Google Patents
Circuit boardInfo
- Publication number
- JP2738603B2 JP2738603B2 JP3150105A JP15010591A JP2738603B2 JP 2738603 B2 JP2738603 B2 JP 2738603B2 JP 3150105 A JP3150105 A JP 3150105A JP 15010591 A JP15010591 A JP 15010591A JP 2738603 B2 JP2738603 B2 JP 2738603B2
- Authority
- JP
- Japan
- Prior art keywords
- conductor
- weight
- circuit
- circuit conductor
- circuit board
- 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
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- Manufacturing Of Printed Wiring (AREA)
- Parts Printed On Printed Circuit Boards (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は混成集積回路装置等に使
用される回路基板の改良に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a circuit board used for a hybrid integrated circuit device or the like.
【０００２】[0002]
【従来の技術】従来、半導体素子等の能動部品や抵抗
器、コンデンサ等の受動部品を多数搭載し、所定の電子
回路を構成するようになした混成集積回路装置は、通
常、内部にタングステン(W) 、モリブデン(Mo)、マンガ
ン(Mn)等の高融点金属から成る配線導体を埋設した絶縁
基体の外表面に銅(Cu)から成る回路導体をその一部が前
記配線導体と接続するようにして被着させた構造の回路
基板を準備し、次に前記回路基板の表面に半導体素子や
コンデンサ、抵抗器等を載置させるとともに各々の電極
端子を回路導体に半田(Sn-Pb合金) 等を介し接合させる
ことによって形成されている。2. Description of the Related Art Conventionally, a hybrid integrated circuit device which mounts a large number of active components such as a semiconductor element and a plurality of passive components such as a resistor and a capacitor to form a predetermined electronic circuit usually has a tungsten (Tungsten) inside. W), molybdenum (Mo), a circuit conductor made of copper (Cu) on the outer surface of an insulating base in which a wiring conductor made of a high melting point metal such as manganese (Mn) is embedded, and a part of which is connected to the wiring conductor. Prepare a circuit board having a structure adhered in the following manner, and then place a semiconductor element, a capacitor, a resistor, etc. on the surface of the circuit board and solder each electrode terminal to a circuit conductor (Sn-Pb alloy) It is formed by joining through such as.
【０００３】尚、かかる従来の混成集積回路装置等に使
用される回路基板は一般にセラミックスの積層技術及び
スクリーン印刷等の厚膜技術を採用することによって製
作されており、具体的には以下の方法によって製作され
る。A circuit board used in such a conventional hybrid integrated circuit device is generally manufactured by employing a ceramic laminating technique and a thick film technique such as screen printing. Produced by
【０００４】即ち、まず、アルミナ(Al 2 O 3 ) 、シ
リカ(SiO2 ) 、マグネシア(MgO) 、カルシア(CaO) 等の
電気絶縁性に優れたセラミックス原料粉末に有機溶剤、
溶媒を添加混合して複数枚のセラミック生シートを得る
とともに該各セラミック生シートの上下面にタングステ
ン、モリブデン、マンガン等の高融点金属粉末から成る
導電ペーストを従来周知のスクリーン印刷等の厚膜手法
を採用することによって所定パターンに印刷塗布する。[0004] First, an organic solvent is added to a ceramic raw material powder such as alumina (Al 2 O 3 ), silica (SiO 2 ), magnesia (MgO), and calcia (CaO) which has excellent electrical insulation properties.
A solvent is added and mixed to obtain a plurality of ceramic raw sheets, and a conductive paste made of a high melting point metal powder such as tungsten, molybdenum, manganese or the like is formed on the upper and lower surfaces of each ceramic raw sheet by a conventionally known thick film method such as screen printing. Is applied in a predetermined pattern by printing.
【０００５】次に前記各セラミック生シートを積層
し、積層体を得るとともにこれを約1500℃の温度で焼成
し、内部及び表面にタングステン、モリブデン、マンガ
ン等の高融点金属から成る配線導体を有する絶縁基体を
得る。Next, the respective ceramic green sheets are laminated to obtain a laminate, which is fired at a temperature of about 1500 ° C., and has a wiring conductor made of a refractory metal such as tungsten, molybdenum, manganese or the like inside and on the surface. Obtain an insulating substrate.
【０００６】そして最後に前記絶縁基体の外表面に、
銅(Cu)粉末に有機溶剤、溶媒を添加混合して得た銅ペー
ストを従来周知のスクリーン印刷法によりその一部が前
記配線導体と接続するようにして塗布させるとともにこ
れを中性雰囲気( 窒素雰囲気)中、約900 ℃の温度で焼
成し、銅粉末を絶縁基体及び配線導体上に被着させるこ
とによって製品としての回路基板となる。Finally, on the outer surface of the insulating substrate,
A copper paste obtained by adding and mixing an organic solvent and a solvent to copper (Cu) powder is applied by a well-known screen printing method so that a part of the copper paste is connected to the wiring conductor, and the paste is applied to a neutral atmosphere (nitrogen atmosphere). (Atmosphere) at a temperature of about 900 ° C., and a copper powder is deposited on the insulating substrate and the wiring conductor to obtain a circuit board as a product.
【０００７】[0007]
【発明が解決しようとする課題】しかしながら、この従
来の回路基板は絶縁基体の外表面に銅ペーストを塗布
し、これを中性雰囲気( 窒素雰囲気)中で焼成して銅か
ら成る回路導体を有する回路基板を得る際、焼成雰囲気
中には通常、銅ペーストに含まれる有機溶剤、溶媒の焼
失を良好とするために7ppm程度の酸素が含有されてお
り、該酸素の含有量の制御は極めて困難で、含有酸素量
が少ないと絶縁基体と銅粉末との界面にアルミン酸銅(C
uAl 2 O 3 ) の析出量が少なくなって回路導体を絶縁基
体に強固に被着させることができず、また含有酸素量が
多いと銅から成る回路導体の表面に酸化物膜が形成さ
れ、回路導体に半導体素子や抵抗器等を半田を介して接
合することが不可となる欠点を有していた。However, this conventional circuit board has a circuit conductor made of copper by applying a copper paste to the outer surface of an insulating base and firing it in a neutral atmosphere (nitrogen atmosphere). When obtaining a circuit board, the firing atmosphere usually contains an organic solvent contained in the copper paste, about 7 ppm of oxygen in order to improve the burning off of the solvent, and it is extremely difficult to control the oxygen content. If the oxygen content is low, copper aluminate (C
The amount of precipitation of uAl 2 O 3 ) is small, and the circuit conductor cannot be firmly adhered to the insulating base.If the oxygen content is large, an oxide film is formed on the surface of the circuit conductor made of copper, There is a disadvantage that it is impossible to join a semiconductor element, a resistor, and the like to a circuit conductor via solder.
【０００８】[0008]
【課題を解決するための手段】本発明の回路基板は、タ
ングステン、モリブデン、マンガンの少なくとも１種か
ら成る配線導体を設けた絶縁基体の外表面に、銀が50乃
至80重量％、パラジウムが３乃至25重量％から成る銀−
パラジウムを主成分とする金属にガラス成分を0.2 乃至
8.0 重量％、ビスマスを2.5 〜25重量％含有させて形成
される回路導体をその一部が前記配線導体と接触するよ
うにして被着させたことを特徴とするものである。According to a circuit board of the present invention, 50 to 80% by weight of silver and 3% of palladium are provided on an outer surface of an insulating substrate provided with a wiring conductor made of at least one of tungsten, molybdenum and manganese. Silver consisting of ~ 25% by weight
Palladium-based metal with a glass content of 0.2 to
It is characterized in that a circuit conductor formed by containing 8.0% by weight and 2.5 to 25% by weight of bismuth is applied so that a part thereof is in contact with the wiring conductor.
【０００９】[0009]
【実施例】次に本発明を添付図面に基づき詳細に説明す
る。図１は本発明の回路基板を説明するための一部拡大
断面図であり、1 は電気絶縁性の材料から成る絶縁基体
である。BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 is a partially enlarged sectional view for explaining a circuit board of the present invention, and 1 is an insulating base made of an electrically insulating material.
【００１０】前記絶縁基体1 は、例えばアルミナセラミ
ックス等の電気絶縁材料から成り、アルミナ(Al 2 O
3 ) 、シリカ(SiO2 ) 、マグネシア(MgO) 、カルシア
(CaO) 等のセラミックス原料粉末に有機溶剤、溶媒を添
加混合して泥漿状となすとともにこれをドクターブレー
ド法を採用することによってセラミック生シートを得、
しかる後、前記セラミック生シートに適当な穴あけ加工
を施すとともに複数枚積層し、還元雰囲気中、約1500℃
の温度で焼成することによって製作される。The insulating substrate 1 is made of, for example, an electrically insulating material such as alumina ceramics, and is made of alumina (Al 2 O).
3 ), silica (SiO 2 ), magnesia (MgO), calcia
An organic solvent is added to a ceramic raw material powder such as (CaO), a solvent is added and mixed to form a slurry, and a ceramic raw sheet is obtained by employing a doctor blade method,
Thereafter, the ceramic green sheet is subjected to an appropriate drilling process and a plurality of the sheets are laminated, and in a reducing atmosphere, about 1500 ° C.
It is manufactured by firing at a temperature of
【００１１】また前記絶縁基体1 にはその内部から上面
に導出する配線導体2 が設けてあり、該配線導体2 はタ
ングステン、モリブデン、マンガンの少なくとも1 種よ
り形成されている。The insulating substrate 1 is provided with a wiring conductor 2 extending from the inside to the upper surface, and the wiring conductor 2 is formed of at least one of tungsten, molybdenum, and manganese.
【００１２】前記配線導体2 はタングテン、モリブデ
ン、マンガンの粉末に有機溶剤、溶媒を添加混合して導
体ペーストを作り、該導体ペーストを前記セラミック生
シートの上下面にスクリーン印刷等により所定パターン
に印刷塗布させておくことによって絶縁基体1 の内部及
び表面に被着形成される。The wiring conductor 2 is prepared by adding and mixing an organic solvent and a solvent to powder of tungsten, molybdenum, and manganese to form a conductor paste, and printing the conductor paste on the upper and lower surfaces of the ceramic green sheet in a predetermined pattern by screen printing or the like. By being applied, it is adhered to the inside and the surface of the insulating base 1.
【００１３】尚、前記配線導体2 はその露出する外表面
にニッケル(Ni)、金(Au)等をメッキ法により層着させて
おくと配線導体2と後述する回路導体3 との電気的導通
を極めて優れたものと成すことができる。従って、配線
導体2 の露出外表面は回路導体2 との電気的導通を良好
とするためにニッケルを1.0 乃至10.0μm 、金を0.5乃
至5.0 μm の厚みにメッキ法により層着させておくこと
が好ましい。If the wiring conductor 2 is coated with nickel (Ni), gold (Au), or the like on its exposed outer surface by plating, the electrical conduction between the wiring conductor 2 and a circuit conductor 3 described later is formed. Can be made extremely excellent. Therefore, the exposed outer surface of the wiring conductor 2 is preferably plated with nickel to a thickness of 1.0 to 10.0 μm and gold to a thickness of 0.5 to 5.0 μm by a plating method in order to improve electric conduction with the circuit conductor 2. preferable.
【００１４】また前記配線導体2 の露出外表面を含む絶
縁基体1 表面には銀−パラジウム(Ag-Pd) を主成分とす
る金属から成る回路導体3 が被着されており、該回路導
体3には半導体素子等の能動部品や抵抗器、コンデンサ
等の受動部品の各電極端子が接続される。A circuit conductor 3 made of a metal containing silver-palladium (Ag-Pd) as a main component is coated on the surface of the insulating base 1 including the exposed outer surface of the wiring conductor 2. Are connected to respective electrode terminals of active components such as semiconductor elements and passive components such as resistors and capacitors.
【００１５】前記回路導体3 は銀、パラジウム等の粉末
にガラス粉末と有機溶剤、溶媒とを添加混合して金属ペ
ーストを作り、該金属ペーストをその一部が配線導体2
と接触するようにして絶縁基体1 の外表面に印刷塗布す
るとともにこれを中性雰囲気中、約850 ℃の温度で焼成
し、絶縁基体1 表面に銀−パラジウム粉末をガラスを介
して被着させることによって絶縁基体1 の外表面に被着
される。この場合、銀−パラジウムを主成分とする金属
から成る回路導体3 はパラジウムが酸化を抑制す作用を
有することから焼成雰囲気中に酸素が多量に含まれてい
ても表面に酸化物膜が形成されることは殆どなく、その
結果、回路導体3 に半導体素子や抵抗器等を半田を介し
て強固に接合させることが可能となる。The circuit conductor 3 is made by adding a glass powder, an organic solvent, and a solvent to a powder of silver, palladium, or the like to form a metal paste.
Is printed and applied to the outer surface of the insulating substrate 1 in such a manner as to come into contact with the substrate, and is baked at a temperature of about 850 ° C. in a neutral atmosphere, and silver-palladium powder is applied to the surface of the insulating substrate 1 via glass. Thereby, it is adhered to the outer surface of the insulating base 1. In this case, an oxide film is formed on the surface of the circuit conductor 3 made of a metal containing silver-palladium as a main component even if the firing atmosphere contains a large amount of oxygen because palladium has an action of suppressing oxidation. As a result, a semiconductor element, a resistor, and the like can be firmly joined to the circuit conductor 3 via solder.
【００１６】また前記銀−パラジウムを主成分とする金
属から成る回路導体3 はガラスを介して絶縁基体1 の外
表面に被着されていることからその被着強度は焼成雰囲
気中に含まれる酸素の量に左右されることなく常に強固
なものとなすことが可能となる。Further, since the circuit conductor 3 made of a metal containing silver-palladium as a main component is adhered to the outer surface of the insulating substrate 1 via glass, the adhesion strength is determined by the oxygen contained in the firing atmosphere. Irrespective of the amount of the solids, it is possible to always be strong.
【００１７】尚、前記銀−パラジウムを主成分とする金
属から成る回路導体３は50乃至80重量％の銀に、パラジ
ウムを３乃至25重量％含んでおり、パラジウムの含有量
が３重量％未満となると回路導体３の表面に酸化物膜が
形成され、回路導体３に半導体素子等を半田を介して強
固に接合させることが困難となるとともに回路導体３に
銀のマイグレーションが起こり、隣接する回路導体３間
が電気的に短絡して回路基板としての機能を失う危険性
がある。またパラジウムの含有量が25重量％を超えると
回路導体３の電気抵抗値が大きくなり、回路基板として
は適さなくなる傾向にある。従って、回路導体３は50乃
至80重量％の銀に、パラジウムを３乃至25重量％含有さ
せておくことが好ましい。The circuit conductor 3 made of a metal mainly composed of silver-palladium contains 50 to 80% by weight of silver and 3 to 25% by weight of palladium, and the content of palladium is less than 3% by weight. As a result, an oxide film is formed on the surface of the circuit conductor 3, making it difficult to firmly join a semiconductor element or the like to the circuit conductor 3 via solder, and at the same time, migration of silver occurs on the circuit conductor 3, so that an adjacent circuit There is a risk that the conductors 3 may be electrically short-circuited and lose their function as a circuit board. On the other hand, if the content of palladium exceeds 25% by weight, the electric resistance of the circuit conductor 3 increases, and it tends to be unsuitable as a circuit board. Therefore, it is preferable that the circuit conductor 3 contains 50 to 80% by weight of silver and 3 to 25% by weight of palladium.
【００１８】また前記回路導体3 に含まれるガラスは、
例えばPbO 、B 2 O 3 、SiO 2 、Al2 O 3 、Na2 O 、K
2 O 、CaO 、ZnO 等から成り、その添加量が0.2 重量％
未満であると回路導体3 を絶縁基体1 に強固に被着させ
るのが困難となり、また8.0重量％を越えると回路導体3
の半田濡れ性( 反応性) が劣化し、回路導体3 に半導
体素子や抵抗器等を半田を介し強固に接合させるのが困
難となる。従って、回路導体3 に添加含有されるガラス
はその添加量を0.2 乃至8.0 重量％の範囲としておくこ
とが好ましい。The glass contained in the circuit conductor 3 is as follows:
For example PbO, B 2 O 3, SiO 2, Al 2 O 3, Na 2 O, K
2 O, CaO, ZnO, etc., the amount of addition is 0.2% by weight
If it is less than 10%, it is difficult to firmly adhere the circuit conductor 3 to the insulating base 1, and if it exceeds 8.0% by weight, the circuit conductor 3
The solder wettability (reactivity) of the circuit conductor 3 is deteriorated, and it becomes difficult to firmly join a semiconductor element, a resistor, or the like to the circuit conductor 3 via solder. Therefore, it is preferable that the amount of glass added to the circuit conductor 3 be in the range of 0.2 to 8.0% by weight.
【００１９】かくしてこの回路基板はその表面に半導体
素子や抵抗器、コンデンサ等が載置され、該半導体素子
等を回路導体に半田を介し接合させることによって混成
集積回路装置となる。Thus, the circuit board has a semiconductor device, a resistor, a capacitor, and the like mounted on the surface thereof, and the semiconductor device and the like are joined to the circuit conductor via solder to form a hybrid integrated circuit device.
【００２０】尚、本発明は上述の実施例に限定されるも
ではなく、本発明の要旨を逸脱しない範囲であれば種々
の変更は可能であり、例えば、銀、パラジウム粉末を含
有する金属ペーストを絶縁基体1 に印刷塗布して回路導
体3を形成する際、ビスマスを2.5 乃至25重量％含有さ
せておくと回路導体3 の絶縁基体1 に対する被着強度が
より強固なものとなる。It should be noted that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention. For example, a metal paste containing silver or palladium powder can be used. Is printed on the insulating base 1 to form the circuit conductor 3, if bismuth is contained in an amount of 2.5 to 25% by weight, the adhesion strength of the circuit conductor 3 to the insulating base 1 becomes stronger.
【００２１】また回路導体3 の外表面に金(Au)から成る
被覆層を0.1 乃至5.0 μm の厚みに層着させておくと回
路導体3 の酸化腐食を有効に防止するとともに半導体素
子や抵抗器、コンデンサ等の電極端子を回路導体3 によ
り強固に接合させることができる。If a coating layer made of gold (Au) is applied to the outer surface of the circuit conductor 3 so as to have a thickness of 0.1 to 5.0 μm, oxidative corrosion of the circuit conductor 3 can be effectively prevented, and the semiconductor element and the resistor can be prevented. In addition, electrode terminals such as capacitors can be more firmly joined to the circuit conductor 3.
【００２２】[0022]
【発明の効果】本発明の回路基板によれば回路導体を銀
が50乃至80重量％、パラジウムが３乃至25重量％から成
る銀−パラジウムを主成分とし、ガラス成分を0.2 乃至
8.0 重量％、ビスマスを2.5 乃至25重量％含有させて形
成される金属で形成したことから回路導体を絶縁基体の
表面に被着させる際、その焼成雰囲気中に含まれる酸素
の量が多くても少なくても常に表面に酸化物膜の存在し
ない回路導体を絶縁基体の外表面に強固に被着させるこ
とが可能となり、混成集積回路装置等に使用される回路
基板として極めて有用となる。According to the circuit board of the present invention, the circuit conductor is mainly composed of silver-palladium composed of 50 to 80% by weight of silver and 3 to 25% by weight of palladium, and has a glass component of 0.2 to 50% by weight.
When the circuit conductor is applied to the surface of the insulating substrate, the firing atmosphere is large even if the amount of oxygen contained in the firing atmosphere is large, because the metal is formed by containing 8.0% by weight and bismuth containing 2.5 to 25% by weight of bismuth. At least, a circuit conductor having no oxide film on its surface can be firmly adhered to the outer surface of the insulating base, which is extremely useful as a circuit board used in a hybrid integrated circuit device or the like.
【図１】本発明にかかる回路基板を説明するための一部
拡大断面図である。FIG. 1 is a partially enlarged cross-sectional view for explaining a circuit board according to the present invention.
１・・・絶縁基体 ２・・・配線導体 ３・・・回路導体 ４・・・被覆層 DESCRIPTION OF SYMBOLS 1 ... Insulating base 2 ... Wiring conductor 3 ... Circuit conductor 4 ... Cover layer
Claims (1)
なくとも１種から成る配線導体を設けた絶縁基体の外表
面に、銀が50乃至80重量％、パラジウムが３乃至25重量
％から成る銀−パラジウムを主成分とする金属にガラス
成分を0.2 乃至8.0 重量％、ビスマスを2.5 〜25重量％
含有させて形成される回路導体をその一部が前記配線導
体と接触するようにして被着させたことを特徴とする回
路基板。1. An outer surface of an insulating substrate provided with a wiring conductor made of at least one of tungsten, molybdenum, and manganese has 50 to 80% by weight of silver and 3 to 25% by weight of palladium.
% Silver-palladium-based metal to glass
0.2 to 8.0% by weight of component, 2.5 to 25% by weight of bismuth
A circuit board, wherein a circuit conductor formed to be contained is applied so that a part thereof is in contact with the wiring conductor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3150105A JP2738603B2 (en) | 1991-06-21 | 1991-06-21 | Circuit board |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3150105A JP2738603B2 (en) | 1991-06-21 | 1991-06-21 | Circuit board |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04372191A JPH04372191A (en) | 1992-12-25 |
| JP2738603B2 true JP2738603B2 (en) | 1998-04-08 |
Family
ID=15489613
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3150105A Expired - Lifetime JP2738603B2 (en) | 1991-06-21 | 1991-06-21 | Circuit board |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2738603B2 (en) |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS4957369A (en) * | 1972-10-04 | 1974-06-04 | ||
| JPS59112681A (en) * | 1982-12-20 | 1984-06-29 | 株式会社日立製作所 | Ceramic circuit board |
| JPS59178793A (en) * | 1983-03-30 | 1984-10-11 | 株式会社日立製作所 | Ceramic printed circuit board |
| JPS60167398A (en) * | 1984-02-09 | 1985-08-30 | 松下電器産業株式会社 | Multilayer circuit board and method of producing same |
-
1991
- 1991-06-21 JP JP3150105A patent/JP2738603B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04372191A (en) | 1992-12-25 |
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