JP2001102709A - Ceramic circuit board - Google Patents
Ceramic circuit boardInfo
- Publication number
- JP2001102709A JP2001102709A JP27686199A JP27686199A JP2001102709A JP 2001102709 A JP2001102709 A JP 2001102709A JP 27686199 A JP27686199 A JP 27686199A JP 27686199 A JP27686199 A JP 27686199A JP 2001102709 A JP2001102709 A JP 2001102709A
- Authority
- JP
- Japan
- Prior art keywords
- circuit board
- metal
- metal circuit
- solder
- layer
- 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.)
- Pending
Links
Landscapes
- Combinations Of Printed Boards (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、セラミック基板に
金属回路板をロウ付けにより接合したセラミック回路基
板に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic circuit board in which a metal circuit board is joined to a ceramic substrate by brazing.
【０００２】[0002]
【従来の技術】近年、パワーモジュール用基板やスイッ
チングモジュール用基板等の回路基板として、セラミッ
ク基板上に被着させたメタライズ金属層に銀−銅合金等
のロウ材を介して銅等から成る金属回路板を接合させた
セラミック回路基板、あるいはセラミック基板上に銀−
銅共晶合金にチタン、ジルコニウム、ハフニウムまたは
その水素化物を添加した活性金属ロウ材を介して銅等か
ら成る金属回路板を直接接合させたセラミック回路基板
が用いられている。2. Description of the Related Art In recent years, as a circuit board such as a power module board or a switching module board, a metallized metal layer adhered on a ceramic substrate is formed of a metal made of copper or the like via a brazing material such as a silver-copper alloy. A ceramic circuit board with a circuit board bonded, or silver
A ceramic circuit board is used in which a metal circuit board made of copper or the like is directly joined to a copper eutectic alloy via an active metal brazing material obtained by adding titanium, zirconium, hafnium or a hydride thereof.
【０００３】かかるセラミック回路基板、例えば、セラ
ミック基板上に被着させたメタライズ金属層にロウ材を
介して銅等から成る金属回路板を接合させたセラミック
回路基板は、一般に酸化アルミニウム質焼結体、窒化ア
ルミニウム質焼結体、窒化珪素質焼結体、ムライト質焼
結体等の電気絶縁性のセラミックス材料から成るセラミ
ック基板の表面にメタライズ金属層を被着させておき、
該メタライズ金属層に銅等の金属材料からなる金属回路
板を銀ロウ等のロウ材を介しロウ付けすることによって
形成されており、具体的には、例えば、セラミック基板
が酸化アルミニウム質焼結体からなる場合には、酸化ア
ルミニウム、酸化珪素、酸化マグネシウム、酸化カルシ
ウム等の原料粉末に適当な有機バインダー、可塑剤、溶
剤等を添加混合して泥漿状と成すとともにこれを従来周
知のドクターブレード法やカレンダーロール法等のテー
プ成形技術を採用して複数のセラミックグリーンシート
を得、次に前記セラミックグリーンシート上にタングス
テンやモリブデン等の高融点金属粉末に適当な有機バイ
ンダー、可塑剤、溶剤を添加混合して得た金属ペースト
をスクリーン印刷法等の厚膜形成技術を採用することに
よって所定パターンに印刷塗布し、次に前記金属ペース
トが所定パターンに印刷塗布されたセラミックグリーン
シートを必要に応じて上下に積層するとともに還元雰囲
気中、約１６００℃の温度で焼成し、セラミックグリー
ンシートと金属ペーストを焼結一体化させて表面にメタ
ライズ金属層を有する酸化アルミニウム質焼結体から成
るセラミック基板を形成し、最後に前記セラミック基板
表面のメタライズ金属層上に銅等から成る所定パターン
の金属回路板を間に銀ロウ等のロウ材を挟んで載置させ
るとともにこれを還元雰囲気中、約９００℃の温度に加
熱してロウ材を溶融させ、該溶融したロウ材でメタライ
ズ金属層と金属回路板とを接合することによって製作さ
れている。[0003] Such a ceramic circuit board, for example, a ceramic circuit board in which a metal circuit board made of copper or the like is joined to a metallized metal layer adhered on the ceramic board via a brazing material, is generally made of an aluminum oxide sintered body. A metallized metal layer is applied to the surface of a ceramic substrate made of an electrically insulating ceramic material such as an aluminum nitride sintered body, a silicon nitride sintered body, a mullite sintered body, etc.
The metallized metal layer is formed by brazing a metal circuit board made of a metal material such as copper through a brazing material such as silver brazing. Specifically, for example, a ceramic substrate is made of an aluminum oxide sintered body. In the case of consisting of, a raw material powder such as aluminum oxide, silicon oxide, magnesium oxide and calcium oxide is mixed with an appropriate organic binder, a plasticizer, a solvent and the like to form a slurry and the mixture is formed into a slurry by a well-known doctor blade method. A plurality of ceramic green sheets are obtained by adopting a tape forming technique such as or a calender roll method, and then an appropriate organic binder, a plasticizer, and a solvent are added to the high melting point metal powder such as tungsten or molybdenum on the ceramic green sheets. The metal paste obtained by mixing is subjected to a predetermined pattern by employing a thick film forming technology such as screen printing. Then, the ceramic green sheets, on which the metal paste is printed and applied in a predetermined pattern, are laminated one on top of the other as necessary and fired at a temperature of about 1600 ° C. in a reducing atmosphere. To form a ceramic substrate made of an aluminum oxide sintered body having a metallized metal layer on the surface, and finally a metal circuit board of a predetermined pattern made of copper or the like on the metallized metal layer on the surface of the ceramic substrate. And a brazing material such as a silver brazing material is interposed therebetween and heated in a reducing atmosphere at a temperature of about 900 ° C. to melt the brazing material, and the metallized metal layer and the metal circuit board are melted with the molten brazing material. It is manufactured by joining.
【０００４】なお、前記メタライズ金属層及び金属回路
板の露出表面には酸化腐蝕を有効に防止するとともに金
属回路板に半導体素子等の電子部品を半田等の接着材を
介して強固に接続させるために、ニッケル等の耐蝕性に
優れ、かつ半田等の接着材に対し濡れ性が良い金属がメ
ッキ法等の技術を用いることによって所定厚みに被着さ
れている。In order to effectively prevent oxidative corrosion on the metallized metal layer and the exposed surface of the metal circuit board, and to firmly connect electronic components such as semiconductor elements to the metal circuit board via an adhesive such as solder. In addition, a metal having excellent corrosion resistance such as nickel and having good wettability with respect to an adhesive such as solder is applied to a predetermined thickness by using a technique such as a plating method.
【０００５】また前記金属回路板への電子部品の接続
は、まず金属回路板上に半田粉末に有機溶剤、溶媒を添
加混合して形成した半田ペーストを従来周知のスクリー
ン印刷法等の印刷技術を用いることによって所定パター
ンに印刷塗布し、次にこの印刷塗布した半田ペースト上
に電子部品の電極を載置当接させ、しかる後、これを所
定温度（約１８０℃）に加熱し、半田ペーストの有機溶
剤、溶媒等を揮散させるとともに半田を溶融させ、該溶
融した半田により金属回路板と電子部品の電極とを接合
させることによって行われている。[0005] The connection of the electronic components to the metal circuit board is performed by printing a solder paste formed by adding and mixing an organic solvent and a solvent to the solder powder on the metal circuit board by a printing technique such as screen printing. By using the solder paste, a predetermined pattern is printed and applied, and then the electrodes of the electronic component are placed and abutted on the printed and applied solder paste, and then heated to a predetermined temperature (approximately 180 ° C.). It is performed by evaporating an organic solvent, a solvent, and the like, melting the solder, and joining the metal circuit board and the electrode of the electronic component with the melted solder.
【０００６】[0006]
【発明が解決しようとする課題】しかしながら、この従
来のセラミック回路基板においては、金属回路板に電子
部品の電極を接続させる半田が金属回路板上に半田ペー
ストをスクリーン印刷法により印刷塗布することによっ
て配されており、その厚みは３０μｍ乃至５０μｍと薄
い。そのため金属回路板に電子部品の電極を半田を介し
て接続させた後、金属回路板と電子部品に熱が作用した
場合、金属回路板と電子部品との間に両者の熱膨張係数
の相違に起因する大きな熱応力が発生するとともに該熱
応力が半田に大きく影響して半田にクラック等を発生さ
せてしまい、その結果、半田を介しての金属回路板への
電子部品の接続の信頼性が大きく低下してしまうという
欠点を有していた。However, in this conventional ceramic circuit board, the solder for connecting the electrodes of the electronic components to the metal circuit board is printed and coated with a solder paste on the metal circuit board by a screen printing method. And its thickness is as thin as 30 μm to 50 μm. For this reason, after connecting the electrodes of the electronic component to the metal circuit board via solder, if heat is applied to the metal circuit board and the electronic component, the difference in the thermal expansion coefficient between the metal circuit board and the electronic component may occur. At the same time, a large thermal stress occurs, and the thermal stress greatly affects the solder, causing cracks or the like in the solder. As a result, the reliability of connection of the electronic component to the metal circuit board via the solder is reduced. There was a disadvantage that it was greatly reduced.
【０００７】本発明は上記欠点に鑑み案出されたもの
で、その目的は金属回路板に電子部品を確実、強固に電
気的接続させることができるセラミック回路基板を提供
することにある。The present invention has been made in view of the above-mentioned drawbacks, and an object of the present invention is to provide a ceramic circuit board capable of securely and strongly connecting an electronic component to a metal circuit board.
【０００８】[0008]
【課題を解決するための手段】本発明は、セラミック基
板の上面に金属回路板を取着して成るセラミック回路基
板であって、前記金属回路板の表面に厚さ１００μｍ乃
至２００μｍの半田層を被着させたことを特徴とするも
のである。SUMMARY OF THE INVENTION The present invention is a ceramic circuit board comprising a ceramic circuit board having a metal circuit board attached to an upper surface thereof, wherein a solder layer having a thickness of 100 μm to 200 μm is provided on the surface of the metal circuit board. It is characterized by being attached.
【０００９】本発明のセラミック回路基板によれば、金
属回路板の表面に厚さが１００μｍ乃至２００μｍの半
田層を被着させたことから金属回路板に電子部品の電極
を半田を介して接続させた後、金属回路板と電子部品に
熱が作用し、金属回路板と電子部品との間に両者の熱膨
張係数の相違に起因する大きな熱応力が発生したとして
もその熱応力は半田層を適度に変形させることによって
吸収され、その結果、電子部品の電極は金属回路板に半
田層を介して確実、強固に電気的接続され、電子部品の
金属回路板への電気的接続の信頼性を極めて高いものと
なすことができる。According to the ceramic circuit board of the present invention, since a solder layer having a thickness of 100 μm to 200 μm is applied to the surface of the metal circuit board, the electrodes of the electronic components are connected to the metal circuit board via solder. After that, heat acts on the metal circuit board and the electronic component, and even if a large thermal stress is generated between the metal circuit board and the electronic component due to a difference in the coefficient of thermal expansion between the two, the thermal stress applies to the solder layer. It is absorbed by moderate deformation, and as a result, the electrodes of the electronic component are securely and firmly electrically connected to the metal circuit board via the solder layer, and the reliability of the electrical connection of the electronic component to the metal circuit board is improved. It can be very high.
【００１０】[0010]
【発明の実施の形態】次に、本発明を添付図面に示す実
施例に基づいて詳細に説明する。図１は、本発明のセラ
ミック回路基板の一実施例の断面図を示し、１はセラミ
ック基板、２はメタライズ金属層、３は金属回路板であ
る。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail based on embodiments shown in the accompanying drawings. FIG. 1 is a sectional view of one embodiment of a ceramic circuit board according to the present invention, wherein 1 is a ceramic substrate, 2 is a metallized metal layer, and 3 is a metal circuit board.
【００１１】前記セラミック基板１は四角形状をなし、
その上面にメタライズ金属層２が被着されており、該メ
タライズ金属層２には金属回路板３がロウ付けされてい
る。The ceramic substrate 1 has a square shape,
A metallized metal layer 2 is adhered on the upper surface, and a metal circuit board 3 is brazed to the metallized metal layer 2.
【００１２】前記セラミック基板１は金属回路板３を支
持する支持部材として作用し、酸化アルミニウム質焼結
体、ムライト質焼結体、炭化珪素質焼結体、窒化アルミ
ニウム質焼結体、ムライト質焼結体等の電気絶縁材料で
形成されている。The ceramic substrate 1 functions as a support member for supporting the metal circuit board 3, and is made of aluminum oxide sintered body, mullite sintered body, silicon carbide sintered body, aluminum nitride sintered body, mullite sintered body. It is formed of an electrically insulating material such as a sintered body.
【００１３】前記セラミック基板１は、例えば、酸化ア
ルミニウム質焼結体で形成されている場合は、酸化アル
ミニウム、酸化珪素、酸化マグネシウム、酸化カルシウ
ム等の原料粉末に適当な有機バインダー、可塑剤、溶剤
を添加混合して泥漿状となすとともに該泥漿物を従来周
知のドクターブレード法やカレンダーロール法を採用す
ることによってセラミックグリーンシート（セラミック
生シート）を形成し、次に前記セラミックグリーンシー
トに適当な打ち抜き加工を施し、所定形状となすととも
に必要に応じて複数枚を積層して成形体となし、しかる
後、これを約１６００℃の高温で焼成することによっ
て、あるいは酸化アルミニウム等の原料粉末に適当な有
機溶剤、溶媒を添加混合して原料粉末を調整するととも
に該原料粉末をプレス成形技術によって所定形状に成形
し、しかる後、前記成形体を約１６００℃の温度で焼成
することによって製作される。When the ceramic substrate 1 is formed of, for example, an aluminum oxide sintered body, an organic binder, a plasticizer, and a solvent suitable for a raw material powder such as aluminum oxide, silicon oxide, magnesium oxide, and calcium oxide are used. Is mixed and formed into a slurry, and the slurry is formed into a ceramic green sheet (green ceramic sheet) by employing a conventionally known doctor blade method or calender roll method. A punching process is performed, a predetermined shape is formed, and a plurality of sheets are laminated as necessary to form a molded body. Thereafter, the molded body is fired at a high temperature of about 1600 ° C., or is applied to a raw material powder such as aluminum oxide. The raw material powder is prepared by adding and mixing an organic solvent and a solvent. By molding techniques and molded into a predetermined shape, and thereafter, is manufactured by firing the molded body at a temperature of about 1600 ° C..
【００１４】また前記セラミック基板１はその表面にメ
タライズ金属層２が被着されており、該メタライズ金属
層２は金属回路板３をセラミック基板１にロウ付けする
際の下地金属層として作用する。On the surface of the ceramic substrate 1, a metallized metal layer 2 is adhered. The metallized metal layer 2 acts as a base metal layer when the metal circuit board 3 is brazed to the ceramic substrate 1.
【００１５】前記メタライズ金属層２は、タングステ
ン、モリブデン、マンガン等の高融点金属材料より成
り、例えば、タングステン粉末に適当な有機バインダ
ー、可塑材、溶剤を添加混合して得た金属ペーストを焼
成によってセラミック基板１となるセラミックグリーン
シート（セラミック生シート）の表面に予め従来周知の
スクリーン印刷法により所定パターンに印刷塗布してお
くことによってセラミック基板１の上面に所定パター
ン、所定厚み（１０〜５０μｍ）に被着される。The metallized metal layer 2 is made of a high melting point metal material such as tungsten, molybdenum, manganese, etc., for example. A predetermined pattern and a predetermined thickness (10 to 50 μm) are formed on the upper surface of the ceramic substrate 1 by printing and applying a predetermined pattern on a surface of a ceramic green sheet (ceramic raw sheet) serving as the ceramic substrate 1 in advance by a conventionally known screen printing method. Is adhered to.
【００１６】なお、前記メタライズ金属層２はその表面
にニッケル、金等の良導電性で、耐蝕性及びロウ材との
濡れ性が良好な金属をメッキ法により１μｍ〜２０μｍ
の厚みに被着させておくと、メタライズ金属層２の酸化
腐蝕を有効に防止することができるとともにメタライズ
金属層２と金属回路板３とのロウ付けを極めて強固とな
すことができる。従って、前記メタライズ金属層２の酸
化腐蝕を有効に防止し、メタライズ金属層２と金属回路
板３とのロウ付けを強固となすにはメタライズ金属層２
の表面にニッケル、金等の良導電性で、耐蝕性及びロウ
材との濡れ性が良好な金属を１μｍ〜２０μｍの厚みに
被着させておくことが好ましい。The metallized metal layer 2 is made of a metal having good conductivity, such as nickel or gold, having good corrosion resistance and good wettability with a brazing material on the surface of the metallized metal layer 2 by a plating method of 1 μm to 20 μm.
If the metallized metal layer 2 is adhered to the metallized metal layer 2, the metallized metal layer 2 and the metal circuit board 3 can be extremely firmly brazed. Therefore, the metallized metal layer 2 is effectively prevented from being oxidized and corroded, and the metallized metal layer 2 is hardly brazed between the metallized metal layer 2 and the metal circuit board 3.
It is preferable that a metal having good conductivity, such as nickel and gold, having good corrosion resistance and good wettability with the brazing material is applied to the surface of the metal to a thickness of 1 μm to 20 μm.
【００１７】また前記メタライズ金属層２はその上面に
金属回路板３がロウ材４を介して取着されている。The metallized metal layer 2 has a metal circuit board 3 attached to the upper surface thereof via a brazing material 4.
【００１８】前記金属回路板３は銅やアルミニウム等の
金属材料から成り、セラミック基板１の表面に形成され
たメタライズ金属層２上に金属回路板３を、例えば、銀
ロウ材（銀：７２重量％、銅：２８重量％）やアルミニ
ウムロウ材（アルミニウム：８８重量％、シリコン：１
２重量％）等から成るロウ材４を挟んで載置させ、しか
る後、これを真空中もしくは中性、還元雰囲気中、所定
温度（銀ロウ材の場合は約９００℃、アルミニウムロウ
材の場合は約６００℃）で加熱処理し、ロウ材４を溶融
せしめるとともにメタライズ金属層２の上面と金属回路
板３の下面とに接合させることによってセラミック基板
１の表面に取着されることとなる。The metal circuit board 3 is made of a metal material such as copper or aluminum. The metal circuit board 3 is provided on the metallized metal layer 2 formed on the surface of the ceramic substrate 1 by, for example, a silver brazing material (silver: 72 wt. %, Copper: 28% by weight) and aluminum brazing material (aluminum: 88% by weight, silicon: 1)
2% by weight) and then placed in a vacuum or in a neutral or reducing atmosphere at a predetermined temperature (about 900 ° C. for silver brazing, about 900 ° C. for aluminum brazing) Is heated at about 600 ° C.) to melt the brazing material 4 and join the upper surface of the metallized metal layer 2 and the lower surface of the metal circuit board 3 to be attached to the surface of the ceramic substrate 1.
【００１９】前記銅やアルミニウム等から成る金属回路
板３は、銅やアルミニウム等のインゴット（塊）に圧延
加工法や打ち抜き加工法等、従来周知の金属加工法を施
すことによって、例えば、厚さが５００μｍで、メタラ
イズ金属層２のパターン形状に対応する所定パターン形
状に製作される。The metal circuit board 3 made of copper, aluminum, or the like has a thickness, for example, obtained by subjecting an ingot of copper, aluminum, or the like to a conventionally known metal working method such as a rolling method or a punching method. Is 500 μm, and is manufactured in a predetermined pattern shape corresponding to the pattern shape of the metallized metal layer 2.
【００２０】前記金属回路板３はまた銅から成る場合、
金属回路板３を無酸素銅で形成しておくと、該無酸素銅
はロウ付けの際に銅の表面が銅中に存在する酸素により
酸化されることなくロウ材４との濡れ性が良好となり、
メタライズ金属層２へのロウ材４を介しての接合が強固
となる。従って、前記金属回路板３はこれを無酸素銅で
形成しておくことが好ましい。If the metal circuit board 3 is also made of copper,
When the metal circuit board 3 is formed of oxygen-free copper, the oxygen-free copper has good wettability with the brazing material 4 without being oxidized by the oxygen existing in the copper surface during brazing. Becomes
Bonding to the metallized metal layer 2 via the brazing material 4 is strengthened. Therefore, it is preferable that the metal circuit board 3 is formed of oxygen-free copper.
【００２１】更に前記金属回路板３はその表面にニッケ
ルから成る良導電性で、かつ耐蝕性及びロウ材との濡れ
性が良好な金属をメッキ法により被着させておくと、金
属回路板３と外部電気回路との電気的接続を良好と成す
とともに金属回路板３に半導体素子等の電子部品を半田
を介して強固に接続させることができる。従って、前記
金属回路板３はその表面にニッケルから成る良導電性
で、かつ耐蝕性及びロウ材との濡れ性が良好な金属をメ
ッキ法により被着させておくことが好ましい。Further, when the metal circuit board 3 is coated on its surface with a metal having good conductivity and good corrosion resistance and good wettability with the brazing material by plating, the metal circuit board 3 Good electrical connection between the metal circuit board 3 and an external electric circuit can be achieved, and electronic components such as semiconductor elements can be firmly connected to the metal circuit board 3 via solder. Therefore, it is preferable that the metal circuit board 3 be coated with a metal made of nickel and having good conductivity, good corrosion resistance and good wettability with the brazing material by plating.
【００２２】また前記金属回路板３の表面にニッケルか
ら成るメッキ層を被着させる場合、内部に燐を８〜１５
重量％含有させてニッケル−燐のアモルファス合金とし
ておくとニッケルから成るメッキ層の表面酸化を良好に
防止してロウ材との濡れ性等を長く維持することができ
る。従って、前記金属回路板３の表面にニッケルから成
るメッキ層を被着させる場合、内部に燐を８〜１５重量
％含有させてニッケル−燐のアモルファス合金としてお
くことが好ましい。When a plating layer made of nickel is applied to the surface of the metal circuit board 3, phosphorous is added to the inside of the metal circuit board 3.
When the amorphous alloy of nickel-phosphorus is contained in an amount of 0.5% by weight, the oxidation of the surface of the plating layer made of nickel can be prevented well, and the wettability with the brazing material can be maintained for a long time. Therefore, when a plating layer made of nickel is applied to the surface of the metal circuit board 3, it is preferable to contain 8 to 15% by weight of phosphorus therein to form a nickel-phosphorus amorphous alloy.
【００２３】なお、前記金属回路板３の表面にニッケル
−燐のアモルファス合金からなるメッキ層を被着させる
場合、ニッケルに対する燐の含有量が８重量％未満、あ
るいは１５重量％を超えたときニッケル−燐のアモルフ
ァス合金を形成するのが困難となってメッキ層に半田を
強固に接着させることができなくなる危険性がある。When a plating layer made of a nickel-phosphorus amorphous alloy is deposited on the surface of the metal circuit board 3, when the content of phosphorus with respect to nickel is less than 8% by weight or more than 15% by weight, There is a danger that it becomes difficult to form an amorphous alloy of phosphorus and the solder cannot be firmly bonded to the plating layer.
【００２４】従って、前記金属回路板３の表面にニッケ
ル−燐のアモルファス合金からなるメッキ層を被着させ
る場合にはニッケルに対する燐の含有量を８〜１５重量
％の範囲としておくことが好ましく、好適には１０〜１
５重量％の範囲がよい。Therefore, when a plating layer made of an amorphous alloy of nickel and phosphorus is applied to the surface of the metal circuit board 3, the content of phosphorus relative to nickel is preferably set in the range of 8 to 15% by weight. Preferably 10-1
A range of 5% by weight is good.
【００２５】また、前記金属回路板３の表面に被着され
るニッケルから成るメッキ層は、その厚みが１．５μｍ
未満の場合、金属回路板３の表面をニッケルから成るメ
ッキ層で完全に被覆することができず、金属回路板３の
酸化腐蝕を有効に防止することができなくなる危険性が
あり、また３μｍを超えるとニッケルから成るメッキ層
の内部に内在する内在応力が大きくなってセラミック基
板１に反りや割れ等が発生してしまう。特にセラミック
基板１の厚さが７００μｍ以下の薄いものになった場合
にはこのセラミック基板１の反りや割れ等が顕著となっ
てしまう。従って、前記金属回路板３の表面に被着され
るニッケルから成るメッキ層はその厚みを１．５μｍ〜
３μｍの範囲としておくことが好ましい。The plating layer made of nickel, which is deposited on the surface of the metal circuit board 3, has a thickness of 1.5 μm.
If it is less than 3, the surface of the metal circuit board 3 cannot be completely covered with the plating layer made of nickel, and there is a risk that oxidation corrosion of the metal circuit board 3 cannot be effectively prevented. If it exceeds, the intrinsic stress existing inside the plating layer made of nickel becomes large, and the ceramic substrate 1 will be warped or cracked. In particular, when the thickness of the ceramic substrate 1 is as thin as 700 μm or less, warpage or cracking of the ceramic substrate 1 becomes remarkable. Therefore, the thickness of the plating layer made of nickel deposited on the surface of the metal circuit board 3 is 1.5 μm to
It is preferable to set the range to 3 μm.
【００２６】前記金属回路板３の表面に被着されたニッ
ケルから成るメッキ層の上には更に半田層５が形成され
ており、該半田層５は半導体素子等の電子部品を金属回
路板３に強固に接着させる作用をなす。A solder layer 5 is further formed on the nickel plating layer adhered to the surface of the metal circuit board 3, and the solder layer 5 is used to mount electronic components such as semiconductor elements on the metal circuit board 3. It acts to firmly adhere to the surface.
【００２７】前記半田層５は、錫−鉛共晶合金、錫−鉛
合金、金−錫合金、金−ゲルマニウム合金等の金属から
なり、例えば、錫−鉛共晶合金（錫：６０重量％、鉛：
４０重量％）からなる場合には、錫−鉛共晶合金の粉末
に有機溶剤、溶媒を添加混合して得た半田ペーストを従
来周知のスクリーン印刷等の印刷技法を用いて金属回路
板３の上面に所定パターンに形成される。The solder layer 5 is made of a metal such as a tin-lead eutectic alloy, a tin-lead alloy, a gold-tin alloy, a gold-germanium alloy, and for example, a tin-lead eutectic alloy (tin: 60% by weight). ,lead:
(40% by weight), an organic solvent and a solvent are added to a tin-lead eutectic alloy powder, and a solder paste obtained by mixing the solder paste is printed on the metal circuit board 3 by a conventionally known printing technique such as screen printing. A predetermined pattern is formed on the upper surface.
【００２８】また、前記半田層５はその厚みを１００μ
ｍ乃至２００μｍの範囲としておくことが重要であり、
半田層５の厚みを１００μｍ乃至２００μｍの範囲とし
ておくことによって金属回路板３に電子部品の電極を接
続させた後、金属回路板３と電子部品に熱が作用し、金
属回路板３と電子部品との間に両者の熱膨張係数の相違
に起因する大きな熱応力が発生したとしてもその熱応力
は半田層５を適度に変形させることによって吸収され、
その結果、電子部品の電極は金属回路板３に半田層５を
介して確実、強固に電気的接続され、電子部品の金属回
路板３への電気的接続の信頼性が極めて高いものとな
る。The solder layer 5 has a thickness of 100 μm.
It is important to keep the range between m and 200 μm,
After the electrodes of the electronic components are connected to the metal circuit board 3 by setting the thickness of the solder layer 5 in the range of 100 μm to 200 μm, heat acts on the metal circuit board 3 and the electronic components, and the metal circuit board 3 and the electronic components are heated. Even if a large thermal stress due to the difference in the thermal expansion coefficient between the two occurs, the thermal stress is absorbed by appropriately deforming the solder layer 5,
As a result, the electrodes of the electronic component are securely and firmly electrically connected to the metal circuit board 3 via the solder layer 5, and the reliability of the electrical connection of the electronic component to the metal circuit board 3 is extremely high.
【００２９】なお、前記半田層５は金属回路板３の上面
に半田ペーストをスクリーン印刷等により所定パターン
に印刷塗布する工程と、前記半田ぺーストを一旦、所定
温度（例えば、半田の液相線温度より３０〜５０℃高い
温度）で５〜１０分間予備加熱して半田ペースト中の有
機溶剤、溶媒を大気中に揮散させるとともに半田粉末間
に存在する空気を抜く工程とを複数回、繰り返すことに
よって１００μｍ乃至２００μｍの厚みに被着される。The solder layer 5 is formed by printing and applying a solder paste on the upper surface of the metal circuit board 3 in a predetermined pattern by screen printing or the like, and once applying the solder paste to a predetermined temperature (for example, a liquidus line of the solder). A process of preheating for 5 to 10 minutes at a temperature 30 to 50 ° C. higher than the temperature to volatilize the organic solvent and the solvent in the solder paste into the air and to remove air existing between the solder powders a plurality of times. To a thickness of 100 μm to 200 μm.
【００３０】また前記半田層５はその厚みが１００μｍ
未満であると半田層５で金属回路板３と電子部品との間
に発生する熱応力を良好に吸収することができず半田層
５にクラック等が発生してしまい、また２００μｍを超
えると金属回路板３に電子部品の電極を半田層５を介し
て接続する際、半田が金属回路板３上からセラミック基
板１上に流れ出て隣接する金属回路板３間を短絡させて
しまう。従って、前記金属回路板３上に被着される半田
層５はその厚みが１００μｍ乃至２００μｍの範囲に特
定される。The solder layer 5 has a thickness of 100 μm.
If the thickness is less than 0.5 mm, the thermal stress generated between the metal circuit board 3 and the electronic component cannot be favorably absorbed by the solder layer 5, causing cracks or the like in the solder layer 5. When the electrodes of the electronic components are connected to the circuit board 3 via the solder layer 5, the solder flows from the metal circuit board 3 onto the ceramic substrate 1 and short-circuits the adjacent metal circuit boards 3. Therefore, the thickness of the solder layer 5 applied on the metal circuit board 3 is specified in the range of 100 μm to 200 μm.
【００３１】かくして、上述のセラミック回路基板によ
れば、金属回路板３の上面に被着させた半田層５上に電
子部品の電極を当接させ、しかる後、これを所定温度
（約１８０℃）に加熱し、半田層５を溶融させるととも
に該溶融した半田層５を金属回路板３及び電子部品の電
極に接合させることによって電子部品は金属回路板３に
電気的に接続され、金属回路板３を外部電気回路に接続
すれば電子部品は金属回路板３を介して外部電気回路に
電気的に接続それることとなる。Thus, according to the above-described ceramic circuit board, the electrodes of the electronic component are brought into contact with the solder layer 5 adhered to the upper surface of the metal circuit board 3 and then brought to a predetermined temperature (about 180 ° C.). The electronic component is electrically connected to the metal circuit board 3 by heating to melt the solder layer 5 and joining the melted solder layer 5 to the metal circuit board 3 and the electrodes of the electronic component. If the electronic component 3 is connected to an external electric circuit, the electronic component is electrically connected to the external electric circuit via the metal circuit board 3.
【００３２】なお、本発明は上述の実施例に限定される
ものではなく、本発明の趣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、上述の実施例ではセ
ラミック基板１がアルミニウム質焼結体で形成された例
を示したが、電子部品が多量の熱を発し、この熱を効率
良く除去したい場合にはセラミック基板１を熱伝導率の
高い窒化アルミニウム質焼結体や窒化珪素質焼結体で形
成すれば良く、金属回路板３に高速で電気信号を伝播さ
せたい場合にはセラミック基板１を誘電率の低いムライ
ト質焼結体で形成すれば良い。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 spirit of the present invention. Although an example in which the electronic component generates a large amount of heat and an efficient removal of this heat is described, the ceramic substrate 1 may be formed of an aluminum nitride sintered body having a high thermal conductivity or an aluminum nitride sintered body. The ceramic substrate 1 may be formed of a mullite sintered body having a low dielectric constant when an electric signal is to be propagated to the metal circuit board 3 at high speed.
【００３３】さらに、上述の実施例ではセラミック基板
１の表面に予めメタライズ金属２を被着させておき、該
メタライズ金属層２に金属回路板３をロウ付けしてセラ
ミック回路基板となしたが、これをセラミック基板１の
表面に、例えば、銀−銅共晶合金にチタンもしくは水素
化チタンを２〜５重量％添加した活性金属ロウ材を介し
て直接金属回路板３を取着させてセラミック回路基板を
形成してもよい。Further, in the above-described embodiment, the metallized metal 2 was previously applied to the surface of the ceramic substrate 1 and the metal circuit board 3 was brazed to the metallized metal layer 2 to form a ceramic circuit board. The metal circuit board 3 is directly attached to the surface of the ceramic substrate 1 via an active metal brazing material obtained by adding titanium or titanium hydride to a silver-copper eutectic alloy in an amount of 2 to 5% by weight. A substrate may be formed.
【００３４】[0034]
【発明の効果】本発明のセラミック回路基板によれば、
金属回路板の表面に厚さが１００μｍ乃至２００μｍの
半田層を被着させたことから金属回路板に電子部品の電
極を半田を介して接続させた後、金属回路板と電子部品
に熱が作用し、金属回路板と電子部品との間に両者の熱
膨張係数の相違に起因する大きな熱応力が発生したとし
てもその熱応力は半田層を適度に変形させることによっ
て吸収され、その結果、電子部品の電極は金属回路板に
半田層を介して確実、強固に電気的接続され、電子部品
の金属回路板への電気的接続の信頼性を極めて高いもの
となすことができる。According to the ceramic circuit board of the present invention,
Since a solder layer having a thickness of 100 μm to 200 μm is applied to the surface of the metal circuit board, after the electrodes of the electronic components are connected to the metal circuit board via solder, heat acts on the metal circuit board and the electronic components. However, even if a large thermal stress is generated between the metal circuit board and the electronic component due to a difference in thermal expansion coefficient between the two, the thermal stress is absorbed by appropriately deforming the solder layer, and as a result, The electrodes of the component are securely and firmly electrically connected to the metal circuit board via the solder layer, and the reliability of the electrical connection of the electronic component to the metal circuit board can be made extremely high.
【図１】本発明のセラミック回路基板の一実施例を示す
断面図である。FIG. 1 is a sectional view showing one embodiment of a ceramic circuit board of the present invention.
１・・・・セラミック基板 ２・・・・メタライズ金属層 ３・・・・金属回路板 ５・・・・半田層 1. Ceramic substrate 2. Metallized metal layer 3. Metal circuit board 5. Solder layer
Claims (1)
して成るセラミック回路基板であって、前記金属回路板
の表面に厚さ１００μｍ乃至２００μｍの半田層を被着
させたことを特徴とするセラミック回路基板。1. A ceramic circuit board having a metal circuit board attached to an upper surface of a ceramic substrate, wherein a solder layer having a thickness of 100 μm to 200 μm is applied to the surface of the metal circuit board. Ceramic circuit board.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP27686199A JP2001102709A (en) | 1999-09-29 | 1999-09-29 | Ceramic circuit board |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP27686199A JP2001102709A (en) | 1999-09-29 | 1999-09-29 | Ceramic circuit board |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2001102709A true JP2001102709A (en) | 2001-04-13 |
Family
ID=17575444
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP27686199A Pending JP2001102709A (en) | 1999-09-29 | 1999-09-29 | Ceramic circuit board |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2001102709A (en) |
-
1999
- 1999-09-29 JP JP27686199A patent/JP2001102709A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6787706B2 (en) | Ceramic circuit board | |
| JP2000340912A (en) | Ceramic circuit board | |
| JP4471470B2 (en) | Semiconductor device | |
| JP4646417B2 (en) | Ceramic circuit board | |
| JP4493158B2 (en) | Ceramic circuit board | |
| JP2002232090A (en) | Ceramic circuit board | |
| JP2001068808A (en) | Ceramic circuit board | |
| JP2001210948A (en) | Ceramic circuit board | |
| JP4299421B2 (en) | Manufacturing method of ceramic circuit board | |
| JP3939979B2 (en) | Nitride ceramic copper circuit board and power module | |
| JP4191860B2 (en) | Ceramic circuit board | |
| JP2001024296A (en) | Ceramic circuit board | |
| JP2001102709A (en) | Ceramic circuit board | |
| JP2003324167A (en) | Ceramic circuit board | |
| JP4721533B2 (en) | Ceramic circuit board | |
| JP2001102694A (en) | Ceramic circuit board | |
| JP2001177194A (en) | Ceramic circuit board | |
| JP2002353374A (en) | Ceramic circuit board | |
| JP4427467B2 (en) | Wiring board and electric element module using the same | |
| JP2002057420A (en) | Ceramic circuit board | |
| JP2001094223A (en) | Ceramic circuit board | |
| JP3954912B2 (en) | Manufacturing method of ceramic circuit board | |
| JP2003100983A (en) | Ceramic circuit board | |
| JP2001210923A (en) | Ceramic circuit board | |
| JP2006066752A (en) | Ceramic circuit board |