JP2004319740A - Power semiconductor device and method for manufacturing the same - Google Patents

Power semiconductor device and method for manufacturing the same Download PDF

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JP2004319740A
JP2004319740A JP2003111236A JP2003111236A JP2004319740A JP 2004319740 A JP2004319740 A JP 2004319740A JP 2003111236 A JP2003111236 A JP 2003111236A JP 2003111236 A JP2003111236 A JP 2003111236A JP 2004319740 A JP2004319740 A JP 2004319740A
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power semiconductor
semiconductor device
conductor
flexible conductor
terminal
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Masanobu Nozawa
正信 野澤
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Fuji Electric Co Ltd
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Fuji Electric Holdings Ltd
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Abstract

<P>PROBLEM TO BE SOLVED: To improve the yield by avoiding troubles that accompany the soldering of conductors for connecting a power semiconductor chip, the circuit pattern on an insulating substrate, and external lead terminals, as incorporated in a package. <P>SOLUTION: In this power semiconductor device, an IGBT3 (power semiconductor chip) is mounted on a package metal base substrate 1 with an insulating substrate 2 sandwiched in between, and then connecting conductors are wired in the device in between the IGBT upper electrode, the circuit pattern on the insulating substrate 2, and external lead terminals 5 led out of a housing 4. In this device, the connecting conductors are flexible conductors 10 comprising annealed copper fine lines formed into bundles, strands, or braids, and each conductor 10 has conductor terminals 10a at both ends, laid on and soldered to members they are designed to connect to. Tensile stress due to thermal contraction that occurs in the soldering process is absorbed by the flexible conductors 10 for the prevention of damage such as detachment or chipping of soldered connections. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、インバータ装置に適用するＩＧＢＴモジュールなどを対象とするパワー半導体装置、およびその製造方法に関する。
【０００２】
【従来の技術】
頭記したＩＧＢＴ（Ｉｎｓｕｌａｔｅｄ Ｇａｔｅ Ｂｉｐｏｌａｒ Ｔｒａｎｓｉｓｔｏｒ） モジュールとして、パッケージの金属ベース板上に絶縁基板を介してパワー半導体チップをマウントした上で、該半導体チップの上面電極，前記絶縁基板の回路パターンと外囲ケースから引き出した外部導出端子との間に配線する接続導体として、銅合金製のリードフレーム（板状導体）を採用して配線抵抗，およびジュール発熱を低減するようにした構成のものが知られている（例えば、特許文献１参照。）。
図７は上記のように接続導体にリードフレームを用いて内部配線したＩＧＢＴモジュールの組立構造を表す図であり、図において１はパッケージの金属ベース板（銅板）、２は金属ベース板１の上面に搭載した絶縁基板（例えば、セラミック板の両面に銅パターンを直接接合したＤｉｒｅｃｔ Ｂｏｎｄｉｎｇ Ｃｏｐｐｅｒ 基板）、３は絶縁基板２の上にコレクタ電極面を下に向けてマウントしたＩＧＢＴ、４は金属ベース板１に組み合わせたパッケージの外囲ケース（樹脂モールドケース）、５は外囲ケース４に一体成形して外部に引き出したコレクタＣ，エミッタＥ，およびゲートＧに対応する外部導出端子、６は絶縁基板２の回路パターン（ＩＧＢＴ３のコレクタ電極を接続した回路パターン）とＩＧＢＴ３の上面のエミッタ電極およびゲート電極と前記の各外部導出端子５との間に配線したリードフレーム（接続導体）である。なお、７はヒートシンクとして金属ベース板１の下面に取り付けた放熱フィンである。
【０００３】
次に、図７に示したＩＧＢＴモジュールの構造において、リードフレーム６を配線の相手側部材に接合する際の半田接合工程を図８で説明する。図示例はＩＧＢＴ３の上面のエミッタ電極と外部導出端子５（エミッタＣの端子）との間に、逆Ｕ字形に屈曲形成したリードフレーム６を半田接合により配線したものである。なお、図中で絶縁基板２は、セラミック板２ａの両面に銅回路パターン２ｂ，２ｃを直接接合したＤｉｒｅｃｔ Ｂｏｎｄｉｎｇ Ｃｏｐｐｅｒ 基板であり、ＩＧＢＴ３はコレクタ電極を下向けに絶縁基板２の銅回路パターン２ｂに半田マウントされている。
ここで、リードフレーム６を配線する際には、ＩＧＢＴ３のエミッタ電極面および外部導出端子５の脚部上面に半田層８（半田板あるいはペースト状半田）を挟んでリードフレーム６の両端脚部を重ね、さらにリードフレーム６の中央部の上面に重り９を載せてリードフレームが転倒しないように定位置に加圧保持した上で、この仮組立体を不活性ガス雰囲気の炉内に搬入して半田接合を行う。なお、炉内温度は半田の溶融温度よりも１０〜３０℃高い温度に設定して半田接合を行うようにしている。
【０００４】
【特許文献１】
特開２００２−７６２５４号公報
【０００５】
【発明が解決しようとする課題】
ところで、前記のようにＩＧＢＴモジュールの内部配線用接続導体としてリードフレームを用い、このリードフレームを図８で述べたような方法で半田接合した従来構成では、その半田接合の工程で次記のような問題点が発生する。
すなわち、リードフレーム６はその板厚，幅をＩＧＢＴ３のサイズ，通電容量に合わせて設定し、一例として板厚０．５ｍｍ，幅７ｍｍの銅合金製になる導体板（剛体）を用いている。
そのために、リードフレーム６の半田接合（半田の溶融→凝固）の際に生じる熱収縮で引張応力がＩＧＢＴ３チップに加わり、これが原因で半田接合部の剥離，チップ割れなどのダメージを引き起こす懸念がある。また、図８で述べたようにリードフレーム６をＩＧＢＴ３のチップ上面と外部導出端子５の脚部上面との間に跨がって載せた仮組立の状態で炉内に搬入して半田接合を行った場合に、ＩＧＢＴ３と外部導出端子５とでは伝熱条件の相違からリードフレーム６との間に挟んだ半田層８が溶融するまでに時間の差が生じ、これが原因でリードフレーム６が定位置からずれた位置に接合されてしまうといった不具合が発生することも認められている。
【０００６】
本発明は上記の点に鑑みなされたものであり、その目的は前記課題を解決し、改良して製品歩留りの向上を図ったパワー半導体装置，およびその製造方法を提供することにある。
【０００７】
【課題を解決するための手段】
上記目的を達成するために、本発明によれば、パッケージの金属ベース板上に絶縁基板を介してパワー半導体チップをマウントした上で、該半導体チップの上面電極，前記絶縁基板の回路パターンと外囲ケースから引き出した外部導出端子との間に接続導体を配線したパワー半導体装置において、
前記接続導体を可撓導体としてその両端を配線の相手側部材に接合する（請求項１）ものとし、具体的には次記のような態様で実現する。
（１） 可撓導体には軟銅などの細線を素線とした束線，撚線，編組線などを用い、その導体の両端に結合した端子を介して配線の相手側部材に接合する（請求項２）。
【０００８】
（２） 可撓導体に周面に熱収縮チューブなどの軟質な絶縁被覆を施しておく（請求項３）。
上記のように内部配線用の接続導体として可撓導体を用いることにより、図８で述べたような半田接合の際に生じる熱収縮を可撓導体自身の変形により吸収して半田接合部の剥離，チップ割れなどのダメージ発生を回避できる。さらに、可撓導体に軟質な絶縁被覆を施しておくことで、接続導体の可撓性を阻害することなしに接続導体が他のチップなどに接触して短絡するなどのトラブルを安全に回避できる。
【０００９】
また、前記の可撓導体を相手側部材に半田接合して内部配線する方法として、本発明によれば、可撓導体の両端端子をそれぞれ配線相手側部材の接合面に半田層を挟んで重ねた上で、各端子の上に重りを乗せて接合位置に加圧保持し、この仮組立状態で不活性ガス雰囲気の炉内に搬入して半田接合を行うものとする（請求項４）。
この方法によれば、半田接合工程で可撓導体の両端と相手側部材との間に挟んだ半田層の溶融に時間差があっても、その影響を受けることなく可撓導体の両端の端子を個別に定位置に加圧保持して半田接合することができる。
【００１０】
【発明の実施の形態】
以下、本発明の実施の形態を図１〜図６に示す実施例に基づいて説明する。
図１は本発明の実施例によるＩＧＢＴモジュールの組立構造図であり、基本的な構造は図７と同様であるが、絶縁基板２の回路パターン，ＩＧＢＴ３のチップ上面電極と外部導出端子５との間に配線する接続導体として、この実施例では図７のリードフレーム６に代えて可撓導体１０を使用し、その両端に結合した導体端子１０ａを介して配線の相手側部材に半田付けするなどして導電接合するようにしている。
【００１１】
ここで、用いる可撓導体１０としては、図２に示すように軟銅などの細線を素線として多数本の素線１０ｂを束ねたもの、また図３のように多数本の素線を撚り合わせた撚線１０ｃ、あるいは図示してないが多数本の素線で編んだ平編組線などを採用し、図４（ａ），（ｂ） で示すように可撓導体１０の両端に通常の圧着端子と同様に導体端子１０ａを嵌合した上で、端子１０ａの筒部を押し潰して可撓導体１０と端子１０ａとの間を電気的，機械的に圧着接合させる。なお、可撓導体１０として撚線あるいは平編組線を用いることにより、外部から配線を通じてモジュールに侵入するノイズを低減させることができる。
【００１２】
なお、可撓導体１０の断面積は、同容量のＩＧＢＴモジュールにおいて、ＩＧＢＴと外部導出端子との間を複数本のワイヤボンディングで接続した場合におけるワイヤの合計断面積以上であることが望ましい。また、同様にリードフレーム６で接続した場合におけるリードフレームの断面積と同等であればよい。
また、図５（ａ），（ｂ） は図２，図３に示した可撓導体１０の外周に絶縁被覆として軟質な絶縁チューブを被覆した応用実施例を示す。この絶縁チューブ１１は、可撓導体１０をモジュール内部に配線した状態で、撓んだ可撓導体が他の半導体チップ，接続導体などに接触して短絡するのを防ぐ役目を果たすもので、例えば耐熱性のある熱収縮チューブが採用できる。なお、熱収縮チューブを用いる場合には、端子１０ａを取り付ける前に可撓導体にチューブを挿入しておき、端子を結合した後に熱を加えてチューブを熱収縮させるようにする。
【００１３】
次に、前記の可撓導体１０を接続導体として、半田接合によりＩＧＢＴモジュールに内部配線する際の半田接合する製造方法を図６により説明する。すなわち、配線の相手側部材であるＩＧＢＴ３の上面電極，および外部導出端子５の脚部の上に半田層８（半田板あるいはペースト状の半田クリーム）を挟んで可撓導体１０の端子１０ａを載せ、さらに両端の各端子１０ａにその上に重り９を載せて端子１０ａを所定の接合位置に加圧保持させる。次にこの仮組立状態のまま炉内に搬入し、ここで炉内温度を半田層８の溶融温度よりも１０〜３０℃高い温度に設定して半田接合を行う。
【００１４】
この方法により、炉内での半田接合工程で可撓導体１０の両端部に挟んだ半田層８が溶融するまでの時間に差があっても、その影響が他端の半田接合部に波及するおそれがなく、可撓導体１０の両端端子１０ａを個々にあらかじめ指定した位置に安定よく半田接合できる。
【００１５】
【発明の効果】
以上述べたように、本発明によれば、パッケージの金属ベース板上に絶縁基板を介してパワー半導体チップをマウントした上で、該半導体チップの上面電極，前記絶縁基板の回路パターンとパッケージの外囲ケースから引き出した外部導出端子との間に接続導体を内部配線したパワー半導体装置において、
前記接続導体を可撓導体としてその両端を配線の相手側部材に接合したことにより、接続導体に剛性のあるリードフレームを採用した従来構成で問題となっていた半田接合部の剥離，チップ割れなどのダメージ発生を回避して安定よく接合でき、これにより製品歩留りの向上化が図れる。
【００１６】
また、前記の可撓導体に軟質な絶縁被覆を施すことで安全性が向上する。
さらに、前記の接続導体を相手側部材に半田接合して内部配線する際の方法として、可撓導体の両端に結合した端子をそれぞれ配線相手側部材の接合面に半田層を挟んで重ねた上で、各端子の上に重りを乗せて定位置に加圧保持し、この仮組立状態で不活性ガス雰囲気の炉内に搬入して半田接合することにより、可撓導体の両端に結合した端子を所定の位置に合わせて安定よく半田接合できる。
【図面の簡単な説明】
【図１】本発明の実施例によるパワー半導体装置の組立構造図
【図２】図１における可撓導体の一実施例の構成図
【図３】撚線を採用した可撓導体の構成図
【図４】図２に示した可撓導体を製造する工程図で、（ａ），（ｂ） はそれぞれ可撓導体と端子との分解状態，および可撓導体に端子を結合した状態を表す図
【図５】可撓導体の周面に絶縁被覆を施した実施例の構造図で、（ａ），（ｂ） はそれぞれ図２，図３の可撓導体に絶縁チューブを被覆した状態を表す図
【図６】本発明の実施例による可撓導体の両端を相手側部材に半田接合して内部配線する際の工程説明図
【図７】接続導体にリードフレームを用いた従来のパワー半導体装置の組立構造図
【図８】図７におけるリードフレームの両端を相手側部材に半田接合して内部配線する際の工程説明図
【符号の説明】
１ 金属ベース板
２ 絶縁基板
２ｂ 回路パターン
３ ＩＧＢＴ（パワー半導体チップ）
５ 外部導出端子
８ 半田層
９ 重り
１０ 可撓導体
１０ａ 導体端子[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a power semiconductor device for an IGBT module or the like applied to an inverter device and a method for manufacturing the same.
[0002]
[Prior art]
As an IGBT (Insulated Gate Bipolar Transistor) module described above, a power semiconductor chip is mounted on a metal base plate of a package via an insulating substrate, and then a top electrode of the semiconductor chip, a circuit pattern of the insulating substrate, and a surrounding area. As a connection conductor to be wired between the external lead-out terminal drawn out of the case, there is known a configuration in which a lead frame (plate-like conductor) made of a copper alloy is adopted to reduce wiring resistance and Joule heat. (For example, see Patent Document 1).
FIG. 7 is a view showing an assembly structure of the IGBT module in which the connection conductors are internally wired using a lead frame as described above. In FIG. 7, 1 is a metal base plate (copper plate) of the package, and 2 is an upper surface of the metal base plate 1 An insulating substrate (for example, a Direct Bonding Copper substrate in which a copper pattern is directly bonded to both surfaces of a ceramic plate) mounted on the substrate 3, an IGBT 3 mounted on the insulating substrate 2 with the collector electrode face down, and a metal base plate 4 An outer case (resin mold case) of the package combined with 1, 5 is an external lead-out terminal corresponding to the collector C, the emitter E, and the gate G formed integrally with the outer case 4 and drawn out, 6 is an insulating substrate 2 (a circuit pattern to which the collector electrode of the IGBT 3 is connected) and the emitter electrode on the upper surface of the IGBT 3 and A lead frame (connection conductor) that wiring between the external lead terminals 5 of the gate electrode. Reference numeral 7 denotes a radiation fin mounted on the lower surface of the metal base plate 1 as a heat sink.
[0003]
Next, in the structure of the IGBT module shown in FIG. 7, a solder joining step for joining the lead frame 6 to a mating member of the wiring will be described with reference to FIG. In the illustrated example, a lead frame 6 bent in an inverted U-shape is wired by soldering between the emitter electrode on the upper surface of the IGBT 3 and the external lead-out terminal 5 (terminal of the emitter C). In the figure, an insulating substrate 2 is a Direct Bonding Copper substrate in which copper circuit patterns 2b and 2c are directly bonded to both surfaces of a ceramic plate 2a, and an IGBT 3 is provided on the copper circuit pattern 2b of the insulating substrate 2 with the collector electrode facing downward. Solder mounted.
Here, when wiring the lead frame 6, both ends of the lead frame 6 are placed on the emitter electrode surface of the IGBT 3 and the upper surface of the leg of the external lead-out terminal 5 with the solder layer 8 (solder plate or solder paste) interposed therebetween. After stacking and placing a weight 9 on the upper surface of the central part of the lead frame 6 and holding the lead frame in a fixed position so that the lead frame does not fall over, the temporary assembly is carried into a furnace in an inert gas atmosphere. Perform solder bonding. The temperature in the furnace is set at a temperature higher by 10 to 30 ° C. than the melting temperature of the solder, so that the solder joining is performed.
[0004]
[Patent Document 1]
JP-A-2002-76254 [0005]
[Problems to be solved by the invention]
By the way, in the conventional configuration in which the lead frame is used as the connection conductor for the internal wiring of the IGBT module and the lead frame is soldered by the method described with reference to FIG. 8 as described above, the soldering process is as follows. Problems arise.
That is, the thickness and width of the lead frame 6 are set according to the size and the current carrying capacity of the IGBT 3, and as an example, a conductor plate (rigid body) made of a copper alloy having a thickness of 0.5 mm and a width of 7 mm is used.
For this reason, tensile stress is applied to the IGBT3 chip due to thermal shrinkage generated at the time of solder joining of the lead frame 6 (solder → solidification of the solder), which may cause damage such as peeling of the solder joint and chip cracking. . Further, as described in FIG. 8, the lead frame 6 is loaded into the furnace in a temporary assembly state in which the lead frame 6 is placed between the upper surface of the chip of the IGBT 3 and the upper surface of the leg of the external lead-out terminal 5, and soldering is performed. In this case, there is a time difference between the IGBT 3 and the external lead-out terminal 5 until the solder layer 8 sandwiched between the lead frame 6 and the IGBT 3 melts due to a difference in heat transfer conditions. It is also recognized that a problem such as joining at a position shifted from the position occurs.
[0006]
The present invention has been made in view of the above points, and an object of the present invention is to provide a power semiconductor device which solves the above-mentioned problems and which is improved to improve the product yield, and a method of manufacturing the same.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, a power semiconductor chip is mounted on a metal base plate of a package via an insulating substrate, and an upper electrode of the semiconductor chip and a circuit pattern of the insulating substrate are externally connected. In a power semiconductor device in which a connection conductor is wired between the external lead-out terminal drawn out of the surrounding case,
The connection conductor is a flexible conductor and both ends thereof are joined to a counterpart member of the wiring (Claim 1). Specifically, the connection conductor is realized in the following manner.
(1) A bundled, twisted, or braided wire made of a thin wire of soft copper or the like is used as a flexible conductor, and the flexible conductor is joined to a counterpart member of the wiring via terminals connected to both ends of the conductor (claim) Item 2).
[0008]
(2) A flexible insulating coating such as a heat-shrinkable tube is applied to the peripheral surface of the flexible conductor (claim 3).
By using the flexible conductor as the connection conductor for the internal wiring as described above, the heat shrinkage generated at the time of the solder joining as described in FIG. In addition, the occurrence of damage such as chip breakage can be avoided. Further, by applying a soft insulating coating to the flexible conductor, it is possible to safely avoid a trouble such as a short circuit caused by the connection conductor coming into contact with another chip or the like without hindering the flexibility of the connection conductor. .
[0009]
According to the present invention, as a method of soldering the flexible conductor to a counterpart member and performing internal wiring, according to the present invention, the both ends of the flexible conductor are overlapped with a bonding layer of the wiring counterpart member with a solder layer interposed therebetween. Then, a weight is placed on each terminal and held at the bonding position under pressure. Then, in this temporarily assembled state, the terminal is carried into a furnace in an inert gas atmosphere to perform solder bonding (claim 4).
According to this method, even if there is a time difference in the melting of the solder layer sandwiched between both ends of the flexible conductor and the counterpart member in the solder joining step, the terminals at both ends of the flexible conductor are not affected by the time difference. Solder bonding can be performed individually while maintaining the pressure at a fixed position.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the examples shown in FIGS.
FIG. 1 is an assembly structure diagram of an IGBT module according to an embodiment of the present invention. The basic structure is the same as that of FIG. 7, but the circuit pattern of the insulating substrate 2, the chip upper surface electrode of the IGBT 3 and the external lead-out terminal 5 are shown. In this embodiment, a flexible conductor 10 is used in place of the lead frame 6 shown in FIG. 7 as a connection conductor to be wired therebetween, and is soldered to a mating member of the wiring via conductor terminals 10a connected to both ends thereof. To perform conductive bonding.
[0011]
Here, as the flexible conductor 10 to be used, as shown in FIG. 2, a thin wire of soft copper or the like is used as a wire and a number of wires 10b are bundled, or as shown in FIG. 3, a number of wires are twisted. 4a, or a flat braided wire (not shown) woven from a number of strands, and is usually crimped to both ends of the flexible conductor 10 as shown in FIGS. 4 (a) and 4 (b). After fitting the conductor terminal 10a in the same manner as the terminal, the cylindrical portion of the terminal 10a is crushed to electrically and mechanically press-fit the flexible conductor 10 and the terminal 10a. In addition, by using a stranded wire or a flat braided wire as the flexible conductor 10, it is possible to reduce noise that enters the module through wiring from the outside.
[0012]
It is desirable that the cross-sectional area of the flexible conductor 10 be equal to or larger than the total cross-sectional area of the wires when the IGBT and the external lead-out terminal are connected by a plurality of wire bondings in the IGBT module having the same capacity. Similarly, the cross-sectional area may be equal to the cross-sectional area of the lead frame when connected by the lead frame 6.
FIGS. 5A and 5B show an application example in which a flexible insulating tube is coated as an insulating coating on the outer periphery of the flexible conductor 10 shown in FIGS. The insulating tube 11 serves to prevent the bent flexible conductor from coming into contact with another semiconductor chip, a connection conductor, or the like and short-circuiting when the flexible conductor 10 is wired inside the module. A heat-shrinkable tube having heat resistance can be used. When a heat-shrinkable tube is used, the tube is inserted into the flexible conductor before attaching the terminal 10a, and after the terminals are connected, heat is applied to thermally shrink the tube.
[0013]
Next, a description will be given of a manufacturing method in which the flexible conductor 10 is used as a connection conductor and soldered when the internal wiring is performed on the IGBT module by soldering, with reference to FIG. That is, the terminal 10a of the flexible conductor 10 is placed on the upper surface electrode of the IGBT 3 which is a mating member of the wiring and the leg of the external lead-out terminal 5 with the solder layer 8 (solder plate or paste-like solder cream) interposed therebetween. A weight 9 is placed on each terminal 10a at both ends, and the terminal 10a is pressed and held at a predetermined joint position. Next, the pre-assembled state is carried into the furnace, where the temperature in the furnace is set to a temperature higher by 10 to 30 ° C. than the melting temperature of the solder layer 8, and soldering is performed.
[0014]
According to this method, even if there is a difference in the time until the solder layer 8 sandwiched between the both ends of the flexible conductor 10 is melted in the solder joining process in the furnace, the influence spreads to the solder joint at the other end. There is no danger, and both end terminals 10a of the flexible conductor 10 can be individually and stably soldered to predetermined positions.
[0015]
【The invention's effect】
As described above, according to the present invention, the power semiconductor chip is mounted on the metal base plate of the package via the insulating substrate, and then the upper electrode of the semiconductor chip, the circuit pattern of the insulating substrate and the outside of the package are mounted. In a power semiconductor device in which a connection conductor is internally wired between an external lead-out terminal drawn out of an enclosure case,
Since the connection conductor is a flexible conductor and both ends thereof are joined to a mating member of the wiring, peeling of a solder joint, chip breakage, and the like, which are problems in the conventional configuration using a rigid lead frame as the connection conductor, have been made. The bonding can be stably performed while avoiding the occurrence of damage, thereby improving the product yield.
[0016]
Further, by applying a soft insulating coating to the flexible conductor, safety is improved.
Further, as a method of performing internal connection by soldering the connection conductor to a mating member, a terminal coupled to both ends of a flexible conductor is overlapped with a bonding layer of the mating member with a solder layer interposed therebetween. A terminal is attached to each end of the flexible conductor by placing a weight on each terminal and holding it under pressure in a fixed position, and carrying it in a furnace in an inert gas atmosphere in this tentatively assembled state and soldering it. Can be stably soldered by adjusting the position to a predetermined position.
[Brief description of the drawings]
1 is an assembly structure diagram of a power semiconductor device according to an embodiment of the present invention; FIG. 2 is a configuration diagram of one embodiment of a flexible conductor in FIG. 1; FIG. 3 is a configuration diagram of a flexible conductor employing a stranded wire; 4 (a) and 4 (b) are views showing a disassembled state of the flexible conductor and the terminal and a state where the terminal is connected to the flexible conductor, respectively. 5A and 5B are structural diagrams of an embodiment in which an insulating coating is applied to a peripheral surface of a flexible conductor, and FIGS. 5A and 5B show a state where an insulating tube is coated on the flexible conductor of FIGS. FIG. 6 is an explanatory view of a process when soldering both ends of a flexible conductor to a counterpart member and internally wiring according to the embodiment of the present invention. FIG. 7 is a conventional power semiconductor device using a lead frame as a connection conductor. FIG. 8 is an internal wiring diagram of FIG. 7 in which both ends of the lead frame are soldered to mating members. Step illustration during EXPLANATION OF REFERENCE NUMERALS
Reference Signs List 1 metal base plate 2 insulating substrate 2b circuit pattern 3 IGBT (power semiconductor chip)
5 External lead-out terminal 8 Solder layer 9 Weight 10 Flexible conductor 10a Conductor terminal

Claims (4)

パッケージの金属ベース板上に絶縁基板を介してパワー半導体チップをマウントした上で、該半導体チップの上面電極，前記絶縁基板の回路パターンとパッケージの外囲ケースから引き出した外部導出端子との間に接続導体を内部配線したパワー半導体装置において、
前記接続導体を可撓導体としてその両端を配線の相手側部材に接合したことを特徴とするパワー半導体装置。After mounting the power semiconductor chip on the metal base plate of the package via the insulating substrate, the upper electrode of the semiconductor chip, the circuit pattern of the insulating substrate and the external lead-out terminal drawn out of the outer case of the package. In a power semiconductor device in which connection conductors are internally wired,
A power semiconductor device wherein the connection conductor is a flexible conductor and both ends are joined to a member on the other side of the wiring. 可撓導体が軟銅などの細線を素線とした束線，撚線，編組線のいずれかであり、その両端に結合した端子を介して配線の相手側部材に接合したことを特徴とする請求項１に記載のパワー半導体装置。The flexible conductor is any one of a bundled wire, a stranded wire, and a braided wire made of a thin wire such as soft copper, and is joined to a mating member of the wiring via terminals connected to both ends thereof. Item 2. The power semiconductor device according to item 1. 可撓導体に軟質な絶縁被覆を施したことを特徴とする請求項１または２に記載のパワー半導体装置。3. The power semiconductor device according to claim 1, wherein a flexible insulating coating is applied to the flexible conductor. 請求項１ないし３のいずれかの項に記載のパワー半導体装置の製造方法であって、可撓導体の両端に結合した端子をそれぞれ配線相手側部材の接合面に半田層を挟んで重ねた上で、各端子の上に重りを乗せて定位置に加圧保持し、この仮組立状態で不活性ガス雰囲気の炉内に搬入して半田接合することを特徴とするパワー半導体装置の製造方法。4. The method for manufacturing a power semiconductor device according to claim 1, wherein the terminals coupled to both ends of the flexible conductor are respectively overlapped on the joint surfaces of the wiring mating members with a solder layer interposed therebetween. A method of manufacturing a power semiconductor device, comprising: placing a weight on each terminal, holding the terminal in a fixed position under pressure, carrying in a furnace in an inert gas atmosphere in this tentatively assembled state, and soldering the terminal.
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