JP4803834B2 - Zn-Al eutectoid alloy bonding material, method for producing Zn-Al eutectoid alloy bonding material, bonding method using Zn-Al eutectoid alloy bonding material, and Zn-Al eutectoid alloy bonding material Semiconductor device - Google Patents

Zn-Al eutectoid alloy bonding material, method for producing Zn-Al eutectoid alloy bonding material, bonding method using Zn-Al eutectoid alloy bonding material, and Zn-Al eutectoid alloy bonding material Semiconductor device Download PDF

Info

Publication number
JP4803834B2
JP4803834B2 JP2007285825A JP2007285825A JP4803834B2 JP 4803834 B2 JP4803834 B2 JP 4803834B2 JP 2007285825 A JP2007285825 A JP 2007285825A JP 2007285825 A JP2007285825 A JP 2007285825A JP 4803834 B2 JP4803834 B2 JP 4803834B2
Authority
JP
Japan
Prior art keywords
mass
bonding material
eutectoid
alloy bonding
eutectoid alloy
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.)
Active
Application number
JP2007285825A
Other languages
Japanese (ja)
Other versions
JP2009113050A (en
Inventor
仁 大貫
優 田代
嘉信 本橋
隆昭 佐久間
キュウ ピン クウ
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ibaraki University NUC
Original Assignee
Ibaraki University NUC
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Ibaraki University NUC filed Critical Ibaraki University NUC
Priority to JP2007285825A priority Critical patent/JP4803834B2/en
Publication of JP2009113050A publication Critical patent/JP2009113050A/en
Application granted granted Critical
Publication of JP4803834B2 publication Critical patent/JP4803834B2/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26—Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/31—Structure, shape, material or disposition of the layer connectors after the connecting process
    • H01L2224/32—Structure, shape, material or disposition of the layer connectors after the connecting process of an individual layer connector
    • H01L2224/321—Disposition
    • H01L2224/32151—Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive
    • H01L2224/32221—Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked
    • H01L2224/32225—Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42—Wire connectors; Manufacturing methods related thereto
    • H01L2224/47—Structure, shape, material or disposition of the wire connectors after the connecting process
    • H01L2224/48—Structure, shape, material or disposition of the wire connectors after the connecting process of an individual wire connector
    • H01L2224/4805—Shape
    • H01L2224/4809—Loop shape
    • H01L2224/48091—Arched
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42—Wire connectors; Manufacturing methods related thereto
    • H01L2224/47—Structure, shape, material or disposition of the wire connectors after the connecting process
    • H01L2224/48—Structure, shape, material or disposition of the wire connectors after the connecting process of an individual wire connector
    • H01L2224/481—Disposition
    • H01L2224/48151—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive
    • H01L2224/48221—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked
    • H01L2224/48225—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation
    • H01L2224/48227—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation connecting the wire to a bond pad of the item
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/73—Means for bonding being of different types provided for in two or more of groups H01L2224/10, H01L2224/18, H01L2224/26, H01L2224/34, H01L2224/42, H01L2224/50, H01L2224/63, H01L2224/71
    • H01L2224/732—Location after the connecting process
    • H01L2224/73251—Location after the connecting process on different surfaces
    • H01L2224/73265—Layer and wire connectors
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/10—Details of semiconductor or other solid state devices to be connected
    • H01L2924/11—Device type
    • H01L2924/13—Discrete devices, e.g. 3 terminal devices
    • H01L2924/1304—Transistor
    • H01L2924/1305—Bipolar Junction Transistor [BJT]
    • H01L2924/13055—Insulated gate bipolar transistor [IGBT]

Landscapes

  • Pressure Welding/Diffusion-Bonding (AREA)

Description

本発明は超塑性現象を利用して対象物を接合するＺｎ−Ａｌ共析系合金接合材、Ｚｎ−Ａｌ共析系合金接合材の製造方法、Ｚｎ−Ａｌ共析系合金接合材を用いた接合方法及びＺｎ−Ａｌ共析系合金接合材を用いた半導体装置に関する。   The present invention uses a Zn-Al eutectoid alloy bonding material that joins objects using a superplastic phenomenon, a method for producing a Zn-Al eutectoid alloy bonding material, and a Zn-Al eutectoid alloy bonding material. The present invention relates to a bonding method and a semiconductor device using a Zn—Al eutectoid alloy bonding material.

パワー半導体素子のダイボンデイング、パワーモジュールにおける半導体素子の実装基板への接合及び実装基板の放熱板への接合にはんだ接合が従来から使用されている。はんだ材としては鉛−錫系合金、Ｚｎ−Ａｌ共晶系合金が周知で、鉛−錫合金系は錫の添加量を調整することにより低温はんだ及び高温はんだを実現し、Ｚｎ−Ａｌ共晶系合金は鉛フリーの高温はんだとして使用されている。Ｚｎ−Ａｌ共晶系合金はんだの場合、液相状態から固相状態に凝固する過程で接合が行われる。この際、体積収縮が発生し、大きな熱応力が発生し、大きな残留応力をもつ固相になる。更に、脆いＺｎ−ｒｉｃｈ相（β相）が大部分を占めるため、強度に問題が残る。これらの点から、Ｚｎ−Ａｌ共晶系合金はんだを用いて接合した場合、温度変化や機械的なストレスによって接合部に亀裂が入り易くなり、接合部の寿命が短くなること、及び過酷なヒートサイクルや外力が加わる用途には適用できなくなるという問題がある。   Conventionally, solder bonding is used for die bonding of power semiconductor elements, bonding of semiconductor elements in power modules to mounting boards, and bonding of mounting boards to heat sinks. Lead-tin alloy and Zn-Al eutectic alloy are well known as solder materials. Lead-tin alloy system realizes low-temperature solder and high-temperature solder by adjusting the amount of tin added, Zn-Al eutectic Alloys are used as lead-free high-temperature solder. In the case of Zn—Al eutectic alloy solder, bonding is performed in the process of solidifying from a liquid phase state to a solid phase state. At this time, volume shrinkage occurs, a large thermal stress is generated, and a solid phase having a large residual stress is obtained. Furthermore, since a brittle Zn-rich phase (β phase) occupies most, there remains a problem in strength. From these points, when joining using Zn-Al eutectic alloy solder, the joint is liable to crack due to temperature change and mechanical stress, shortening the life of the joint, and severe heat There is a problem that it cannot be applied to applications where a cycle or external force is applied.

環境対応ハイブリッド車の燃費向上及びコスト低減には、モータ制御に用いられるインバータ用ＩＧＢＴモジュールの動作温度を高めることが極めて有効である。最高動作温度を現状の１２０℃から２００℃に高めることが実現できれば、冷却装置を水冷方式から空冷方式に変更が可能になり、大幅な軽量化が期待できる。ＩＧＢＴモジュールの２００℃動作の実現に際して、半導体自体には基本的に障害はなく、インバータを構成するＭＯＳ型パワーデバイスのはんだ接合に使用する高温はんだ合金の実現が課題となっている。   Increasing the operating temperature of an inverter IGBT module used for motor control is extremely effective in improving fuel efficiency and reducing costs in an environmentally friendly hybrid vehicle. If it is possible to increase the maximum operating temperature from the current 120 ° C. to 200 ° C., the cooling device can be changed from the water cooling method to the air cooling method, and a significant reduction in weight can be expected. In realizing the 200 ° C. operation of the IGBT module, there is basically no obstacle to the semiconductor itself, and the realization of a high-temperature solder alloy used for solder bonding of the MOS type power device constituting the inverter is an issue.

高温はんだ合金の一例として、１〜７質量％Ａｌ−０．５〜６質量％Ｍｇ−１〜２５質量％Ｓｎ−Ｚｎからなり３００℃程度の融点を有するＺｎ−Ａｌ共晶系合金はんだが提案されている（特許文献１）。
特開平１１−２０７４８７号 As an example of a high-temperature solder alloy, a Zn-Al eutectic alloy solder composed of 1 to 7 mass % Al-0.5 to 6 mass % Mg-1 to 25 mass % Sn-Zn and having a melting point of about 300 ° C is proposed. (Patent Document 1).
JP-A-11-207487

特許文献１に開示されたＺｎ−Ａｌ共晶系合金はんだは、３００℃程度の融点を有し、鉛を使用しない点で環境性に優れた高温はんだであるが、接合に溶融工程及び凝固工程を経る必要があり、接合部が高い脆性を有しているという問題が残されている。   The Zn—Al eutectic alloy solder disclosed in Patent Document 1 is a high-temperature solder having a melting point of about 300 ° C. and excellent in environmental properties in that lead is not used. There remains a problem that the joint has high brittleness.

本発明の目的は鉛フリーで高い融点を有しかつ固相状態で接合が可能なＺｎ−Ａｌ共析系合金接合材を提供することにある。
本発明の他の目的はＺｎ−Ａｌ共析系合金接合材の製造方法を提供することにある。
本発明の別の目的はＺｎ−Ａｌ共析系合金接合材を用いた接合方法を提供することにある。
本発明の更に他の目的はＺｎ−Ａｌ共析系合金接合材を使用した半導体装置を提供することにある。 An object of the present invention is to provide a Zn-Al eutectoid alloy bonding material that is lead-free, has a high melting point, and can be bonded in a solid phase.
Another object of the present invention is to provide a method for producing a Zn—Al eutectoid alloy bonding material.
Another object of the present invention is to provide a bonding method using a Zn-Al eutectoid alloy bonding material.
Still another object of the present invention is to provide a semiconductor device using a Zn—Al eutectoid alloy bonding material.

本発明Ｚｎ−Ａｌ共析系合金接合材の特徴とするところは、１７〜３０質量％Ａｌ−０〜１．５質量％Ｃｕ−０〜０．５質量％Ｍｇ−Ｚｎからなり、超塑性現象を利用して対象物を接合する点にある。Ａｌを１７〜３０質量％にする理由は２５０℃以上の高温で使用できるＺｎ−Ａｌ共析系合金において超塑性を発現するために必要な組成範囲であること、Ｃｕ及びＭｇを添加する理由は強度の向上及び微細組織の安定化を図ることにある。Ｚｎ−Ａｌ共析系合金の強度は温度が上昇すると徐々に低下し、４３０℃を超えると急激に低下する特性を示す。Ｃｕ及びＭｇを添加すると温度上昇に伴う強度の低下を抑制することが可能となる。詳述すると、ＣｕはＡｌ−rich及びＺｎ−rich相の何れにも固溶し、両相の強化（主に固溶強化）に寄与する。Ｍｇは合金の粒界や異相境界に偏析し、粒界や異相境界の移動を抑制する働きがあり、結晶粒組織を微細な状態に保持する効果がある。しかしながら、添加量が多過ぎると延性が低下し脆性が現れる。従って、添加量は０〜１．５質量％Ｃｕ及び０〜０．５質量％Ｍｇが好ましい。このような特徴を有するＺｎ−Ａｌ共析系合金は、等軸粒状の微細組織を有し、２００〜４１０℃の温度領域で超塑性現象を発現し、２８０〜４１０℃から徐冷することによって超塑性を発現しない層状の金属組織に変態するため、この金属組織の変態を利用することによって半導体基体をセラミック基板もしくは金属基板に接合するための接合層を形成する本発明の接合材として使用される。 The Zn-Al eutectoid alloy bonding material of the present invention is characterized by comprising 17-30 mass % Al-0-1.5 mass % Cu-0-0.5 mass % Mg-Zn, and a superplastic phenomenon. It is in the point which joins a target object using. The reason why Al is 17 to 30% by mass is the composition range necessary for developing superplasticity in a Zn-Al eutectoid alloy that can be used at a high temperature of 250 ° C. or higher, and the reason for adding Cu and Mg. The purpose is to improve the strength and stabilize the microstructure. The strength of the Zn—Al eutectoid alloy gradually decreases as the temperature increases, and rapidly decreases when the temperature exceeds 430 ° C. When Cu and Mg are added, it is possible to suppress a decrease in strength accompanying a temperature rise. More specifically, Cu dissolves in both Al-rich and Zn-rich phases and contributes to strengthening of both phases (mainly solid solution strengthening). Mg segregates at the grain boundaries and heterogeneous boundaries of the alloy and has a function of suppressing movement of the grain boundaries and heterophase boundaries, and has the effect of maintaining the crystal grain structure in a fine state. However, when the addition amount is too large, ductility is lowered and brittleness appears. Therefore, the addition amount is preferably 0 to 1.5 mass % Cu and 0 to 0.5 mass % Mg. A Zn—Al eutectoid alloy having such characteristics has an equiaxed granular microstructure, exhibits a superplastic phenomenon in a temperature range of 200 to 410 ° C., and is gradually cooled from 280 to 410 ° C. Since it transforms into a layered metal structure that does not exhibit superplasticity, it is used as a bonding material of the present invention for forming a bonding layer for bonding a semiconductor substrate to a ceramic substrate or a metal substrate by utilizing this metal structure transformation. The

本発明Ｚｎ−Ａｌ共析系合金接合材の製造方法の特徴とするところは、１７〜３０質量％Ａｌ−０〜１．５質量％Ｃｕ−０〜０．５質量％Ｍｇ−Ｚｎ共析系合金を溶解鋳造し、これを２８０〜４１０℃の温度で３０分〜３時間保持した後、−４〜２０℃の水中で急冷する点にある。この処理によって、等軸粒状の微細組織が形成される。急冷後のＺｎ−Ａｌ共析系合金の鋳塊は、半導体とセラミック基板もしくは金属基板との接合材として、更に１５０〜２７０℃の温度範囲において厚さ０．１〜１ｍｍの帯状に圧延加工される。このような組織を持つＺｎ−Ａｌ共析系合金は低変形応力で大きな延性を示す超塑性を生じる。 The feature of the method for producing a Zn-Al eutectoid alloy bonding material of the present invention is that 17-30 mass % Al-0-1.5 mass % Cu-0-0.5 mass % Mg-Zn eutectoid system. The alloy is melt-cast, held at a temperature of 280 to 410 ° C for 30 minutes to 3 hours, and then rapidly cooled in water at -4 to 20 ° C. By this treatment, an equiaxed granular microstructure is formed. The rapidly cooled Zn-Al eutectoid alloy ingot is rolled into a strip of 0.1 to 1 mm in thickness in the temperature range of 150 to 270 ° C as a bonding material between the semiconductor and the ceramic substrate or metal substrate. The A Zn—Al eutectoid alloy having such a structure produces superplasticity exhibiting large ductility at low deformation stress.

本発明Ｚｎ−Ａｌ共析系合金接合材を用いた第１の接合方法の特徴は固相にて対象物を接合することにある。固相には完全な固相と固相と液相が混合した半溶融状態を含み、具体的には次の接合方法がある。
第１の接合方法の特徴とするところは、第１の部材及び第２の部材の接合する面にＺｎまたはＺｎ−Ａｌ系合金の被膜を形成し、第１の部材と第２の部材との間に１７〜３０質量％Ａｌ−０〜１．５質量％Ｃｕ−０〜０．５質量％Ｍｇ−Ｚｎ系からなるＺｎ−Ａｌ共析系合金接合材を介在し、該接合材を加熱して固相状態で接合した後徐冷する点にある。この接合方法は超塑性を１００％利用した固相による接合であるため低変形応力となる。超塑性を発現する組織は強度が低いけれど、接合後の徐冷によって超塑性を発現しない層状の強度の高い金属組織になる。この結果、低変形応力で接合強度の高い接合部を実現することが出来る。
また、第１の部材及び第２の部材がそれぞれ半導体基体及びセラミック基板もしくは金属基板である場合は、半導体基体とセラミック基板もしくは金属基板との間に１７〜３０質量％Ａｌ−０〜１．５質量％Ｃｕ−０〜０．５質量％Ｍｇ−Ｚｎ系からなるＺｎ−Ａｌ共析系合金接合材を介在し、該接合材を２８０〜４１０℃に加熱し、超塑性を発現する状態で１〜３０分間保持した後徐冷する接合方法、又は２００〜２７５℃に加熱し、超塑性を発現する状態で１〜３０分間保持した後、２８０〜４１０℃に昇温後徐冷する接合方法である。
第２の接合方法の特徴とするところは、第１の部材と第２の部材との間に１７〜３０質量％Ａｌ−０〜１．５質量％Ｃｕ−０〜０．５質量％Ｍｇ−Ｚｎ系からなるＺｎ−Ａｌ共析系合金接合材を介在し、該接合材を加熱して半溶融状態にした後徐冷する点にある。この接合方法は超塑性１００％利用することは出来ないが、固液２相で超塑性のような変形が生じる状態で接合するため、第１の接合方法より劣るが共晶系合金を使用する場合に比較して低変形応力となる。接合後の徐冷によって超塑性を発現しない２種類の層状の強度の高い金属組織になる。この結果、低変形応力で接合強度の高い接合部を実現することが出来る。 The feature of the first bonding method using the Zn—Al eutectoid alloy bonding material of the present invention is that the objects are bonded in a solid phase. The solid phase includes a complete solid phase and a semi-molten state in which the solid phase and the liquid phase are mixed. Specifically, there are the following bonding methods.
A feature of the first joining method is that a coating of Zn or a Zn—Al alloy is formed on the surfaces to be joined of the first member and the second member, and the first member and the second member interposing a 17 to 30 wt% Al-0 to 1.5 wt% Cu-0 to 0.5 wt% Mg-Zn consisting based Zn-Al co析系alloy bonding material between, heated the bonding material Then, after joining in the solid phase state, it is gradually cooled. Since this joining method is joining by solid phase using 100% of superplasticity, it becomes low deformation stress. Although the structure exhibiting superplasticity is low in strength, it becomes a layered high-strength metal structure that does not exhibit superplasticity by slow cooling after joining. As a result, it is possible to realize a joint with low deformation stress and high joint strength.
Further, when the first member and the second member are a semiconductor substrate and a ceramic substrate or a metal substrate, respectively, 17-30 mass % Al-0 to 1.5 between the semiconductor substrate and the ceramic substrate or the metal substrate. A Zn—Al eutectoid alloy bonding material composed of mass % Cu-0 to 0.5 mass % Mg—Zn is interposed, and the bonding material is heated to 280 to 410 ° C. to develop superplasticity. In a joining method of holding for 30 minutes and then gradually cooling, or in a joining method of heating to 200 to 275 ° C. and holding for 1 to 30 minutes in a state of developing superplasticity, and then gradually cooling to 280 to 410 ° C. is there.
A feature of the second joining method is that 17 to 30% by mass Al-0 to 1.5% by mass Cu-0 to 0.5% by mass Mg— between the first member and the second member. A Zn—Al eutectoid alloy bonding material made of Zn is interposed, and the bonding material is heated to a semi-molten state and then gradually cooled. Although this joining method cannot be used with 100% superplasticity, it is inferior to the first joining method but uses a eutectic alloy because joining is performed in a state where superplasticity occurs in a solid-liquid two-phase. Compared to the case, the deformation stress is low. Two types of layered high-strength metal structures that do not exhibit superplasticity are formed by slow cooling after joining. As a result, it is possible to realize a joint with low deformation stress and high joint strength.

本発明半導体装置の特徴とするところは、半導体基体、半導体基体に直接またはセラミック基板を介して接合層によって接合された金属基板を備え、接合層が１７〜３０質量％Ａｌ−０〜１．５質量％Ｃｕ−０〜０．５質量％Ｍｇ−Ｚｎ系からなるＺｎ−Ａｌ共析系合金接合材からなり、接合時に超塑性現象を発現し、接合後に超塑性を発現しない金属組織を有する点にある。超塑性接合材を用いて接合するメリットは、接合時には超塑性を利用して固相状態でかつ低変形応力で接合でき、接合後は超塑性を発現せず延性と機械的強度を持つ接合部を実現できることである。接合部が接合後において超塑性を発現しない金属組織になっていることは、過酷なヒートサイクルで使用される半導体装置においては必須の要件である。
半導体基体としては、シリコン、化合物半導体、炭化珪素が使用できる。本発明Ｚｎ−Ａｌ共析系合金接合材の特徴の一つは高い融点を有する点にあり、この点から半導体基体に炭化珪素を使用すると高温動作が可能な半導体装置を実現できる。 A feature of the semiconductor device of the present invention is that it includes a semiconductor substrate, a metal substrate bonded to the semiconductor substrate by a bonding layer directly or via a ceramic substrate, and the bonding layer is 17 to 30% by mass Al-0 to 1.5. It consists of a Zn-Al eutectoid alloy joining material consisting of a mass % Cu-0 to 0.5 mass % Mg-Zn system, and has a metal structure that exhibits a superplastic phenomenon during joining and does not develop superplasticity after joining. It is in. The merit of joining using superplastic joint material is that it can be joined in a solid state with low deformation stress using superplasticity at the time of joining, and after joining, it has ductility and mechanical strength without manifesting superplasticity. Can be realized. It is an essential requirement for a semiconductor device used in a severe heat cycle that the joint has a metal structure that does not exhibit superplasticity after joining.
As the semiconductor substrate, silicon, a compound semiconductor, or silicon carbide can be used. One of the features of the Zn—Al eutectoid alloy bonding material of the present invention is that it has a high melting point. From this point, a semiconductor device capable of high-temperature operation can be realized by using silicon carbide for the semiconductor substrate.

本発明Ｚｎ−Ａｌ共析系合金接合材は１７〜３０質量％Ａｌ−０〜１．５質量％Ｃｕ−０〜０．５質量％Ｍｇ−Ｚｎからなっているため、２５０℃以上の高温で使用でき、かつ超塑性現象を利用して対象物を固相状態で接合することが可能になり、延性があり長寿命の接合部を実現できる。また、本発明Ｚｎ−Ａｌ共析系合金接合材を使用した半導体装置は、接合材が接合時には超塑性を発現し、接合後は超塑性を発現しない金属組織になっているため、過酷なヒートサイクルに耐えかつ長寿命の接合部を実現できる。 Since the Zn-Al eutectoid alloy bonding material of the present invention is composed of 17 to 30 mass % Al-0 to 1.5 mass % Cu-0 to 0.5 mass % Mg-Zn, at a high temperature of 250 ° C or higher. It can be used, and the object can be joined in a solid phase using the superplastic phenomenon, and a ductile and long-life joint can be realized. In addition, the semiconductor device using the Zn—Al eutectoid alloy bonding material of the present invention has a metal structure that exhibits superplasticity during bonding and does not exhibit superplasticity after bonding. A long-life joint that can withstand the cycle can be realized.

本発明の最良の実施形態は、接合する対象物である一対の被接合材の間にＺｎ−Ａｌ共析系合金接合材を介在した状態で加熱してＺｎ−Ａｌ共析系合金接合材に超塑性を発現して固相状態で被接合材を接合し、接合後はＺｎ−Ａｌ共析系合金接合材を徐冷して超塑性を発現しない金属組織にする使い方である。特に、半導体装置の接合材としての用途が本発明Ｚｎ−Ａｌ共析系合金接合材の効果を発揮できる分野である。   In the best mode of the present invention, a Zn-Al eutectoid alloy bonding material is heated by interposing a Zn-Al eutectoid alloy bonding material between a pair of materials to be bonded. This is a method of joining the materials to be joined in a solid state by developing superplasticity and, after joining, gradually cooling the Zn-Al eutectoid alloy joining material to form a metal structure that does not develop superplasticity. In particular, the use as a bonding material for semiconductor devices is a field in which the effect of the Zn—Al eutectoid alloy bonding material of the present invention can be exhibited.

表１に種々の組成を有するＺｎ−Ａｌ共析系合金接合材を準備し、被接合材を接合した後における接合層の延性特性及び強度特性を比較した結果を示す。Ｎｏ．１からＮｏ．９の接合材は表に示す組成の合金を溶解鋳造し、これを２８０〜４１０℃の温度で３０分〜３時間保持した後、−４〜２０℃の水中で急冷して製造したものを被接合材の間に介在して超塑性を発現する温度範囲において固相状態で接合した後徐冷した。Ｎｏ．１０の接合材については表に示す組成の合金を溶製したものを被接合材の間に介在して３６０℃で加熱・溶融後凝固した。   Table 1 shows the results of comparing the ductility characteristics and strength characteristics of the bonding layers after preparing Zn-Al eutectoid alloy bonding materials having various compositions and bonding the materials to be bonded. No. 1 to No. The bonding material of No. 9 was prepared by melting and casting an alloy having the composition shown in the table, holding it at a temperature of 280 to 410 ° C. for 30 minutes to 3 hours, and then rapidly cooling it in water at −4 to 20 ° C. It was annealed after joining in a solid phase in a temperature range in which it was interposed between joining materials and developed superplasticity. No. For the 10 bonding materials, a melted alloy having the composition shown in the table was interposed between the materials to be bonded, heated at 360 ° C. and solidified after melting.

Figure 0004803834
表１から明らかなように、Ｎｏ．１〜３のＺｎ−Ａｌ共析系合金接合材はＣｕを０．１５質量％添加しＭｇを添加しないもので、超塑性を発現する微細粒状組織は高温で強度が低く耐クリープ性も低いが、接合後は超塑性を発現しない層状組織となり強度及び耐クリープ抵抗が大きくなる。Ｎｏ．４〜６のＺｎ−Ａｌ共析系合金接合材はＣｕを０．５質量％、Ｍｇを０．０２質量％それぞれ添加したもので、Ｎｏ．１〜３のＺｎ−Ａｌ共析系合金接合材に比較して超塑性を発現する温度が高くなり、接合後の層状組織はＮｏ．１〜３のＺｎ−Ａｌ共析系合金接合材に比較して強度や耐クリープ抵抗が大きくなる。Ｎｏ．７〜９Ｚｎ−Ａｌ共析系合金接合材はＣｕを１．０質量％、Ｍｇを０．０３質量％それぞれ添加したもので、Ｎｏ．１〜６のＺｎ−Ａｌ共析系合金接合材に比較して超塑性を発現する温度が高くなり、Ｎｏ．１〜６のＺｎ−Ａｌ共析系合金接合材に比較して強度や耐クリープ抵抗が大きい。これに対し、比較例として示したＮｏ．１０のＺｎ−Ａｌ共晶系合金接合材は微細粒状組織でないため超塑性を発現せず、接合後は脆いＺｎ−ｒｉｃｈ相が多いため強度特に衝撃強度が低い。以上のように、本発明Ｚｎ−Ａｌ共析系合金接合材は超塑性を発現して固相状態で接合でき、接合後は強度及び耐クリープ性の点で優れていることが分かる。比較例として示した従来のＺｎ−Ａｌ共晶系合金接合材は超塑性を発現しないため液相が存在する温度範囲での接合となり、接合部の強度は低くなる。
Figure 0004803834
 As is apparent from Table 1, No. 1 to 3 Zn-Al eutectoid alloy joining materials are those in which 0.15% by mass of Cu is added and Mg is not added. The fine granular structure that exhibits superplasticity is low in strength and low in creep resistance at high temperatures. After joining, it becomes a layered structure that does not exhibit superplasticity, and strength and creep resistance increase. No. Nos. 4-6 Zn-Al eutectoid alloy bonding materials were prepared by adding 0.5% by mass of Cu and 0.02% by mass of Mg. As compared with the Zn-Al eutectoid alloy bonding material of 1 to 3, the temperature at which superplasticity is exhibited becomes higher, and the layered structure after bonding is No. 1. Compared with 1 to 3 Zn—Al eutectoid alloy bonding materials, strength and creep resistance are increased. No. The 7-9Zn-Al eutectoid alloy bonding material was prepared by adding 1.0% by mass of Cu and 0.03% by mass of Mg. As compared with the Zn—Al eutectoid alloy bonding materials of 1 to 6, the temperature at which superplasticity is exhibited becomes high. Compared with 1-6 Zn-Al eutectoid alloy bonding materials, the strength and creep resistance are large. On the other hand, No. shown as a comparative example. No. 10 Zn—Al eutectic alloy bonding material does not exhibit superplasticity because it is not a fine grain structure, and after bonding, since there are many brittle Zn-rich phases, its strength, particularly impact strength, is low. As described above, it can be seen that the Zn—Al eutectoid alloy bonding material of the present invention exhibits superplasticity and can be bonded in a solid state, and is excellent in strength and creep resistance after bonding. Since the conventional Zn-Al eutectic alloy bonding material shown as a comparative example does not exhibit superplasticity, bonding is performed in a temperature range in which a liquid phase exists, and the strength of the bonding portion is reduced.

図１は本発明Ｚｎ−Ａｌ共析系合金接合材の製造方法の工程図で、縦軸に処理温度、横軸に時間を採ってＴＭＴ（Thermo−Mechanical Treatment：加工熱処理）線図として示してある。まず、１７〜３０質量％Ａｌ−０〜１．５質量％Ｃｕ−０〜０．５質量％Ｍｇ−Ｚｎからなる組成のＺｎ−Ａｌ共析系合金を準備し、室温から３４５±６５℃まで加熱して所定時間（例えば３０分〜３時間）保持して溶体化処理した後、−４〜２０℃の水中で急冷する。２０℃の水中で急冷したときはそのままの状態で所定時間（例えば１０分〜１時間）保持し、−４℃の水中で急冷したときは急冷後２０〜５０℃の温度に１０分〜１時間保持した後室温に戻す。この処理によって、図２に示す超塑性を発現する等軸粒状の微細組織が形成される。図２（ａ）は２２質量％Ａｌ−０．１５質量％Ｃｕ−Ｚｎ共析系合金接合材の組織を示す電子顕微鏡写真で、平均粒径ｄが０．８７μｍ、１．９μｍ、３．９μｍの場合を示している。図２（ｂ）は２２質量％Ａｌ−１．０質量％Ｃｕ−０．０３質量％Ｍｇ−Ｚｎ共析系合金接合材の組織を示す電子顕微鏡写真である。次に、等軸粒状の微細組織化されたＺｎ−Ａｌ共析系合金を１５０〜２７０℃で加熱しながら圧延して所定厚さ（０．１〜１ｍｍ）に加工する。これによって得られた帯状のＺｎ−Ａｌ共析系合金接合材が出来上がる。接合材として使用するときには、接合個所の面積に応じた寸法に切断して被接合材の間に介在する。 FIG. 1 is a process diagram of a method for producing a Zn—Al eutectoid alloy bonding material according to the present invention, and shows a TMT (Thermo-Mechanical Treatment) diagram with the processing temperature on the vertical axis and the time on the horizontal axis. is there. First, a Zn-Al eutectoid alloy having a composition of 17 to 30% by mass Al-0 to 1.5% by mass Cu-0 to 0.5% by mass Mg-Zn is prepared, and from room temperature to 345 ± 65 ° C. After heating and holding for a predetermined time (for example, 30 minutes to 3 hours) and solution treatment, it is rapidly cooled in water at -4 to 20 ° C. When rapidly cooled in water at 20 ° C., it is maintained for a predetermined time (for example, 10 minutes to 1 hour), and when rapidly cooled in water at −4 ° C., it is rapidly cooled to a temperature of 20 to 50 ° C. for 10 minutes to 1 hour. Return to room temperature after holding. By this process, an equiaxed granular microstructure that exhibits superplasticity shown in FIG. 2 is formed. FIG. 2A is an electron micrograph showing the structure of a 22 mass % Al-0.15 mass % Cu—Zn eutectoid alloy bonding material, with an average particle diameter d of 0.87 μm, 1.9 μm, and 3.9 μm. Shows the case. FIG. 2B is an electron micrograph showing the structure of the 22 mass % Al-1.0 mass % Cu-0.03 mass % Mg-Zn eutectoid alloy bonding material. Next, the equiaxed granular microstructured Zn—Al eutectoid alloy is rolled while being heated at 150 to 270 ° C. to be processed to a predetermined thickness (0.1 to 1 mm). A band-shaped Zn—Al eutectoid alloy bonding material obtained in this way is completed. When used as a bonding material, it is cut into dimensions according to the area of the bonding portion and interposed between the materials to be bonded.

本発明Ｚｎ−Ａｌ共析系合金接合材を用いた第１の接合方法を説明する。まず、接合する第１の部材と第２の部材の接合する面にＺｎまたはＺｎ−Ａｌ系合金の被膜を（ドブ付け法などにより）形成する。第１の部材と第２の部材との間に１７〜３０質量％Ａｌ−０〜１．５質量％Ｃｕ−０〜０．５質量％Ｍｇ−Ｚｎ系からなる板状または箔状のＺｎ−Ａｌ共析系合金接合材を介在し、２８０〜４１０℃（α’領域）または２００〜２７５℃（α＋β領域）の温度領域で１〜３０分加熱して接合材に超塑性を発現して、固相状態で接合する。本発明のＺｎ−Ａｌ共析系合金接合材は２７５℃以下では（α＋β）の２相合金状態が熱力学的に安定相であるので、熱処理後は共析変態により（α＋β）の２相状態になる。２８０〜４１０℃の接合では接合後に徐冷する。２００〜２７０℃の接合では、接合後２８０〜４１０℃の範囲に昇温後徐冷する。これによって、接合材（接合層）は図３に示す超塑性を発現しない層状の金属組織になる。図３（ａ）は２２質量％Ａｌ−０．１５質量％Ｃｕ−Ｚｎ共析系合金接合材を用いて接合した後徐冷した場合の接合部の金属組織を、図３（ｂ）は２２質量％Ａｌ−１．０質量％Ｃｕ−０．０３質量％Ｍｇ−Ｚｎ共析系合金接合材を用いて接合した後徐冷した場合の接合部の金属組織をそれぞれ示す電子顕微鏡写真である。図から分かるように、図２に示す等軸粒状の微細組織が層状の金属組織になっていることが分かる。等軸粒状の微細組織は高温での強度が低くかつ耐クリープ性も低いが、接合によって強度及び耐クリープ性の高い層状の金属組織に変わることにより、強度及び耐クリープ性の高い接合部を実現できる。 A first bonding method using the Zn—Al eutectoid alloy bonding material of the present invention will be described. First, a coating film of Zn or a Zn—Al-based alloy is formed on the surfaces of the first member to be joined and the second member to be joined (by a dobbing method or the like). A plate-like or foil-like Zn— consisting of 17-30 mass % Al-0-1.5 mass % Cu-0-0.5 mass % Mg—Zn system between the first member and the second member. By interposing an Al eutectoid alloy bonding material, and heating in a temperature range of 280 to 410 ° C. (α ′ region) or 200 to 275 ° C. (α + β region) for 1 to 30 minutes, the bonding material exhibits superplasticity, Join in solid state. In the Zn—Al eutectoid alloy bonding material of the present invention, since the two-phase alloy state of (α + β) is a thermodynamically stable phase at 275 ° C. or less, the two-phase state of (α + β) is caused by eutectoid transformation after heat treatment. become. In joining at 280 to 410 ° C., it is gradually cooled after joining. In the joining at 200 to 270 ° C., the temperature is raised in the range of 280 to 410 ° C. after the joining and then gradually cooled. As a result, the bonding material (bonding layer) has a layered metal structure that does not exhibit superplasticity as shown in FIG. FIG. 3 (a) shows the metal structure of the joint when it is annealed using a 22% by mass Al—0.15% by mass Cu—Zn eutectoid alloy bonding material, and FIG. It is an electron micrograph which each shows the metal structure of the junction part when it joins using the mass % Al-1.0 mass % Cu-0.03 mass % Mg-Zn eutectoid system alloy joining material, and it anneals. As can be seen, the equiaxed granular microstructure shown in FIG. 2 is a layered metal structure. The equiaxed granular microstructure has low strength at high temperatures and low creep resistance, but by joining it into a layered metal structure with high strength and creep resistance, a joint with high strength and creep resistance is realized. it can.

本発明Ｚｎ−Ａｌ共析系合金接合材を用いた第２の接合方法を説明する。接合する第１の部材と第２の部材との間に１７〜３０質量％Ａｌ−０〜１．５質量％Ｃｕ−０〜０．５質量％Ｍｇ−Ｚｎ系からなる板状または箔状のＺｎ−Ａｌ共析系合金接合材を介在し、４３０〜４８０℃の温度領域で１〜３０分加熱する。これによって接合材は固相と液相が混在した半溶融状態になる。この状態を所定時間保持した後徐冷する。徐冷により半溶融状態の接合材は凝固するが、このとき図４に示すように等軸粒状の微細組織の固相部分が残り、その後の冷却により２種類の層状組織が混在した金属組織になる。図４は２２質量％Ａｌ−０．１５質量％Ｃｕ−Ｚｎ共析系合金接合材を用いて接合した後徐冷した場合の接合部の金属組織を示す電子顕微鏡写真である。層状組織であるので超塑性を発現しない。従って、半溶融状態で接合しても固相状態で接合する場合に比較すれば多少劣るが、従来例に比較すれば強度及び耐クリープ性の優れた接合部が得られる。 A second bonding method using the Zn—Al eutectoid alloy bonding material of the present invention will be described. Between the first member and the second member to be joined, a plate-like or foil-like material composed of 17-30 mass % Al-0-1.5 mass % Cu-0-0.5 mass % Mg-Zn system. A Zn—Al eutectoid alloy bonding material is interposed and heated in a temperature range of 430 to 480 ° C. for 1 to 30 minutes. As a result, the bonding material is in a semi-molten state in which a solid phase and a liquid phase are mixed. This state is kept for a predetermined time and then slowly cooled. The semi-molten bonding material is solidified by slow cooling. At this time, as shown in FIG. 4, a solid phase portion of an equiaxed granular microstructure remains, and the subsequent cooling results in a metal structure in which two types of layered structures are mixed. Become. FIG. 4 is an electron micrograph showing the metallographic structure of the bonded part when it is bonded using a 22 mass % Al-0.15 mass % Cu-Zn eutectoid alloy bonding material and then slowly cooled. Since it is a layered structure, it does not exhibit superplasticity. Therefore, even if it is joined in the semi-molten state, it is somewhat inferior to the case of joining in the solid phase state, but a joint having excellent strength and creep resistance can be obtained as compared with the conventional example.

図５は本発明Ｚｎ−Ａｌ共析系合金接合材を使用したダイオードを示す。図において、１は底部が閉鎖され上端が開放された例えば銅製の円筒状ヒートシンク、２はダイオード機能を備えたシリコンチップ、３は銅−インバー（鉄ニッケル合金）−銅からなる緩衝板、４は円板部４ａと円板部から垂直に伸びるリード４ｂとからなるリード電極で、円筒状ヒートシンク１の底部上にＺｎ−Ａｌ共析系合金接合材５を介して緩衝板３が、その上にＺｎ−Ａｌ系合金接合材６を介してシリコンチップ２が、その上にＺｎ−Ａｌ共析系合金接合材７を介してリード電極４の円板部４ａが接合されている。シリコンチップ２、緩衝板３及び円板部４ａのＺｎ−Ａｌ共析系合金接合材と接する面にはＮｉ−Ｐめっき膜を形成している。８は円筒状ヒートシンク１内に充填したシリコンゴムである。かかる構成のダイオードは所定数の貫通孔を有する冷却フィンの貫通孔に圧入されて自動車用整流装置に使用される。この種整流装置はエンジンルームに配置され、熱的及び機械的に過酷な環境で使用されることから、高温でかつ機械的強度の高い接合材が要求されている。本発明Ｚｎ−Ａｌ共析系合金接合材を使用することにより、２５０℃以上の高温に耐え、延性と強度を有する接合部を実現できる。この実施例ではシリコンチップを使用した場合を説明したが、シリコンチップの代わりに炭化珪素チップを使用することが出来る。炭化珪素チップは５００℃でも安定した特性を保持できることから、接合材が固液共有状態に相変態する温度近くまで使用可能な高温ダイオードを実現できる。   FIG. 5 shows a diode using the Zn—Al eutectoid alloy bonding material of the present invention. In the figure, 1 is a cylindrical heat sink made of, for example, copper whose bottom is closed and the top is open, 2 is a silicon chip having a diode function, 3 is a buffer plate made of copper-invar (iron nickel alloy) -copper, 4 is A buffer electrode 3 is formed on the bottom of the cylindrical heat sink 1 via a Zn-Al eutectoid alloy bonding material 5 on a lead electrode comprising a disc portion 4a and a lead 4b extending perpendicularly from the disc portion. The silicon chip 2 is bonded via a Zn—Al-based alloy bonding material 6, and the disk portion 4 a of the lead electrode 4 is bonded thereon via a Zn—Al eutectoid-based alloy bonding material 7. A Ni—P plating film is formed on the surfaces of the silicon chip 2, the buffer plate 3, and the disk portion 4 a that are in contact with the Zn—Al eutectoid alloy bonding material. Reference numeral 8 denotes silicon rubber filled in the cylindrical heat sink 1. The diode having such a configuration is press-fitted into a through hole of a cooling fin having a predetermined number of through holes and used in a rectifier for an automobile. Since this type of rectifier is disposed in an engine room and is used in a severely and thermally severe environment, a bonding material having a high temperature and high mechanical strength is required. By using the Zn—Al eutectoid alloy bonding material of the present invention, it is possible to realize a bonded portion that can withstand high temperatures of 250 ° C. or more and has ductility and strength. In this embodiment, the case where the silicon chip is used has been described, but a silicon carbide chip can be used instead of the silicon chip. Since the silicon carbide chip can maintain stable characteristics even at 500 ° C., a high-temperature diode that can be used up to a temperature close to the temperature at which the bonding material is transformed into a solid-liquid shared state can be realized.

図６、図７及び図８は本発明Ｚｎ−Ａｌ共析系合金接合材を用いた３００Ａ級ＩＧＢＴモジュールの平面図及び断面図を示したものである。
図６は本発明の一実施例であり、１個の３００Ａ級モジュール単位の平面図を示したものである。また、図７は図６のＡ−Ａに沿う断面図、図８は図６のＢ−Ｂ線に沿う断面図である。図において、１０１は放熱板及び支持板として機能する金属基板、１０２は金属基板１０１上に２枚並べてＺｎ−Ａｌ共析系合金接合層１０３により固着された例えばＡｌＮからなるセラミックス基板、１０４は各セラミックス基板１０２上に形成した例えばＮｉ／Ｃｕからなる回路層で、回路層１０４は分離された異なる形状を有する３個の部分、即ち、Ｔ字型のコレクタ共通電極となる第１の部分１０４ａ、エミッタ電極となる片状の第２の部分１０４ｂ、ゲート電極となる片状の第３の部分１０４ｃからなり、第１の部分１０４ａが中央部に、第１の部分１０４ａの脚部一側に第２の部分１０４ｂが、他方側に第３の部分１０４ｃが配置されている。第２の部分１０４ｂ及び第３の部分１０４ｃはＮｉ層上にＡｌ層１０５が形成されている。１０６はそのアノード側が回路層１０４の第１の部分１０４ａの脚部上に３個並べてＺｎ−Ａｌ共析系合金接合層１０７を介して接合されたＩＧＢＴチップ、１０８はそのカソード側が第１の部分１０４ａの上辺部上にＺｎ−Ａｌ共析系合金接合層１０９を介して接合されたダイオードチップ、１１０はＩＧＢＴチップ１０６のエミッタ層上に形成したＡｌを主成分とする金属層１１１と第２の部分１０４ｂ上のＡｌ層１０５とを超音波ボンディングによって接続した直径５００μｍＡｌ−０．１〜１質量％Ｘ（Ｃｕ、Ｆｅ、Ｍｎ、Ｍｇ、Ｃｏ、Ｌｉ、Ｐｄ、Ａｇ、Ｈｆから選ばれた少なくとも一種類の金属）ボンディングワイヤ、１１２はＩＧＢＴチップ１０５のゲート層上に形成したＡｌを主成分とする金属層１１３と第３の部分１０４ｃ上のＡｌ層１０５とを超音波ボンディングによって接続した直径５００μｍＡｌ−０．１〜１質量％Ｘ（同上）ボンディングワイヤ、１１４はダイオードチップ１０８のアノード層上に形成したＡｌを主成分とする金属層１１５と第２の部分１０４ｂ上のＡｌ層１０５とを超音波ボンディングによって接続したＡｌ−０．１〜１質量％Ｘ（同上）ボンディングワイヤである。これによって、１枚のセラミックス基板１０２上に３個の並列接続されたＩＧＢＴチップ１０６と１個のダイオードチップ１０８とが逆並列接続された回路要素が形成され、１枚の金属基板１０１上に２個の回路要素が形成される。インバータを構成する場合には、１枚の金属基板１０１上の２個の回路要素を直列接続し、これを３個並列接続して、各回路要素の接続点を交流出力端子に、並列接続点を直流入力端子にすればよい。電流容量を増やすときはＩＧＢＴチップ１０６及びダイオードチップ１０８の並列接続数を増やし、高電圧化するときはＩＧＢＴチップ１０６及びダイオードチップ１０８の直列接続数を増やせばよい。 6, 7 and 8 are a plan view and a cross-sectional view of a 300A class IGBT module using the Zn—Al eutectoid alloy bonding material of the present invention.
FIG. 6 is an embodiment of the present invention, and shows a plan view of one 300A class module unit. 7 is a cross-sectional view taken along line AA in FIG. 6, and FIG. 8 is a cross-sectional view taken along line BB in FIG. In the figure, 101 is a metal substrate that functions as a heat radiating plate and a support plate, 102 is a ceramic substrate made of, for example, AlN, arranged on the metal substrate 101 and fixed by a Zn—Al eutectoid alloy bonding layer 103, and 104 A circuit layer made of, for example, Ni / Cu formed on the ceramic substrate 102, and the circuit layer 104 is separated into three parts having different shapes, that is, a first part 104a serving as a T-shaped collector common electrode, It consists of a piece-like second portion 104b to be an emitter electrode and a piece-like third portion 104c to be a gate electrode. The first portion 104a is located at the center portion and the leg portion of the first portion 104a is located on one side of the leg portion. The second portion 104b and the third portion 104c are arranged on the other side. In the second portion 104b and the third portion 104c, an Al layer 105 is formed on the Ni layer. 106 is an IGBT chip whose anode side is arranged on the legs of the first portion 104a of the circuit layer 104 and bonded via a Zn-Al eutectoid alloy bonding layer 107, and 108 is the first portion on the cathode side. A diode chip 110 is bonded to the upper side portion 104 a via a Zn—Al eutectoid alloy bonding layer 109, and a second metal layer 111 mainly composed of Al formed on the emitter layer of the IGBT chip 106 and the second chip layer 110. 500 μm diameter Al—0.1-1 mass % X (Cu, Fe, Mn, Mg, Co, Li, Pd, Ag, Hf selected at least one selected from the Al layer 105 on the portion 104b by ultrasonic bonding The kind of metal) bonding wire 112 is a metal layer 113 mainly composed of Al formed on the gate layer of the IGBT chip 105 and the third portion 104. Diameter 500μmAl-0.1~1 wt% X (same as above) bonding wires and Al layer 105 was connected by ultrasonic bonding above, 114 metal layer mainly composed of Al formed on the anode layer of the diode chip 108 115 and an Al layer 105 on the second part 104b are Al—0.1 to 1 mass % X (same as above) bonding wires connected by ultrasonic bonding. As a result, a circuit element in which three parallel-connected IGBT chips 106 and one diode chip 108 are connected in reverse parallel is formed on one ceramic substrate 102, and 2 on one metal substrate 101. Circuit elements are formed. When configuring an inverter, two circuit elements on one metal substrate 101 are connected in series, three of them are connected in parallel, and the connection point of each circuit element is used as an AC output terminal. May be used as a DC input terminal. When the current capacity is increased, the number of parallel connections of the IGBT chip 106 and the diode chip 108 is increased, and when the voltage is increased, the number of serial connections of the IGBT chip 106 and the diode chip 108 may be increased.

図９は本発明Ｚｎ−Ａｌ共析系合金接合材を使用した電力用ＭＯＳトランジスタを示す概略断面図である。図において、２１は放熱板及び支持板として機能する金属基板、２２は金属基板２１上にＺｎ−Ａｌ共析系合金接合層２３により固着された例えばＡｌＮからなるセラミックス基板、２４はセラミックス基板２２上にＺｎ−Ａｌ共析系合金接合層２５により固着された電力用ＭＯＳトランジスタ基体、２６、２７及び２８は電力用ＭＯＳトランジスタ基体のアノード領域、カソード領域及びゲート領域に設けられたアルミニウムからなるアノード電極、カソード電極及びゲート電極である。ゲート電極２８は当然のことながら絶縁層２９を介してゲート領域上に設けられている。３０及び３１はカソード電極２７及びゲート電極２８にＺｎ−Ａｌ共析系合金接合層３２及び３３により固着されたカソード外部電極及びゲート外部電極である。これらカソード外部電極３０及びゲート外部電極３１は間に例えば樹脂を充填して一体構造にしてもよい。この実施例の特徴は、カソード電極２７及びゲート電極２８とカソード外部電極３０及びゲート外部電極３１をボンディングワイヤを使用せずに直接接合している点にある。この実施例におけるＭＯＳトランジスタ基体２４はシリコン及び炭化珪素を使用することが出来る。炭化珪素基体を使用する場合には炭化珪素が５００℃でも安定した特性を保持できることから、接合材が固液共有状態に相変態する温度近くまで使用可能な高温ＭＯＳトランジスタを実現できる。   FIG. 9 is a schematic cross-sectional view showing a power MOS transistor using the Zn—Al eutectoid alloy bonding material of the present invention. In the figure, 21 is a metal substrate that functions as a heat sink and a support plate, 22 is a ceramic substrate made of, for example, AlN fixed on the metal substrate 21 by a Zn—Al eutectoid alloy bonding layer 23, and 24 is on the ceramic substrate 22. The power MOS transistor substrate 26, 27 and 28 fixed to each other by a Zn-Al eutectoid alloy bonding layer 25 are anode electrodes made of aluminum provided in the anode region, the cathode region and the gate region of the power MOS transistor substrate. A cathode electrode and a gate electrode. Naturally, the gate electrode 28 is provided on the gate region via the insulating layer 29. Reference numerals 30 and 31 denote a cathode external electrode and a gate external electrode fixed to the cathode electrode 27 and the gate electrode 28 by Zn—Al eutectoid alloy bonding layers 32 and 33, respectively. These cathode external electrode 30 and gate external electrode 31 may be integrated with, for example, a resin filled therebetween. This embodiment is characterized in that the cathode electrode 27 and the gate electrode 28 are directly joined to the cathode external electrode 30 and the gate external electrode 31 without using bonding wires. The MOS transistor base 24 in this embodiment can use silicon and silicon carbide. In the case of using a silicon carbide substrate, since silicon carbide can maintain stable characteristics even at 500 ° C., it is possible to realize a high-temperature MOS transistor that can be used up to a temperature close to the temperature at which the bonding material is transformed into a solid-liquid shared state.

本発明Ｚｎ−Ａｌ共析系合金接合材はＩＧＢＴモジュールに限らず一般のパワーモジュール、ダイオードモジュールなどに使用できる。   The Zn-Al eutectoid alloy bonding material of the present invention can be used not only for IGBT modules but also for general power modules, diode modules and the like.

本発明Ｚｎ−Ａｌ共析系合金接合材の製造方法の工程を示すＴＭＴ線図である。It is a TMT diagram which shows the process of the manufacturing method of this invention Zn-Al eutectoid type alloy joining material. 超塑性を発現するような微細等軸粒状組織化にされた本発明Ｚｎ−Ａｌ共析系合金接合材の組織を示す顕微鏡写真である。It is a microscope picture which shows the structure | tissue of this invention Zn-Al eutectoid type alloy joining material made into the fine equiaxed grain structure which expresses superplasticity. 第１の接合方法において接合後徐冷した本発明Ｚｎ−Ａｌ共析系合金接合材の組織を示す顕微鏡写真である。It is a microscope picture which shows the structure | tissue of this invention Zn-Al eutectoid type alloy bonding material which annealed slowly after joining in the 1st joining method. 第２の接合方法において接合後徐冷した本発明Ｚｎ−Ａｌ共析系合金接合材の組織を示す顕微鏡写真である。It is a microscope picture which shows the structure | tissue of this invention Zn-Al eutectoid type alloy bonding material annealed after joining in the 2nd joining method. 本発明Ｚｎ−Ａｌ共析系合金接合材を使用したダイオードの概略断面図である。It is a schematic sectional drawing of the diode which uses this invention Zn-Al eutectoid type alloy joining material. 本発明Ｚｎ−Ａｌ共析系合金接合材を使用したＩＧＢＴモジュールの概略平面図である。It is a schematic plan view of an IGBT module using the Zn—Al eutectoid alloy bonding material of the present invention. 第６図のＡ−Ａ線に沿う概略断面図である。It is a schematic sectional drawing which follows the AA line of FIG. 第６図のＢ−Ｂに沿う概略断面図である。It is a schematic sectional drawing in alignment with BB of FIG. 本発明Ｚｎ−Ａｌ共析系合金接合材を使用した電力用ＭＯＳトランジスタの概略平面図である。1 is a schematic plan view of a power MOS transistor using a Zn—Al eutectoid alloy bonding material of the present invention.

１・・・円筒状ヒートシンク、２・・・シリコンチップ、３・・・緩衝板、４・・・リード電極、５，６，７・・・Ｚｎ−Ａｌ共析系合金接合材、８・・・シリコンゴム。   DESCRIPTION OF SYMBOLS 1 ... Cylindrical heat sink, 2 ... Silicon chip, 3 ... Buffer plate, 4 ... Lead electrode, 5, 6, 7 ... Zn-Al eutectoid alloy bonding material, ... ·Silicon rubber.

Claims (6)

半導体基体をセラミック基板もしくは金属基板に接合するための接合層を形成する合金接合材であって、前記合金接合材は、１７〜３０質量％Ａｌ−０〜１．５質量％Ｃｕ−０〜０．５質量％Ｍｇ−Ｚｎ系からなり、等軸粒状の微細組織を有し、２００〜４１０℃の温度領域で超塑性現象を発現し、２８０〜４１０℃から徐冷することによって超塑性を発現しない層状の金属組織に変態することを特徴とするＺｎ−Ａｌ共析系合金接合材。 An alloy bonding material for forming a bonding layer for bonding a semiconductor substrate to a ceramic substrate or a metal substrate, wherein the alloy bonding material is 17-30 mass % Al-0-1.5 mass % Cu-0-0. .5 mass % Mg-Zn-based, has an equiaxed granular microstructure, exhibits superplasticity in the temperature range of 200-410 ° C, and develops superplasticity by slow cooling from 280-410 ° C A Zn-Al eutectoid alloy bonding material characterized by being transformed into a layered metal structure that does not. 半導体基体をセラミック基板もしくは金属基板に接合するための合金接合材であって、前記合金接合材は、１７〜３０質量％Ａｌ−０〜１．５質量％Ｃｕ−０〜０．５質量％Ｍｇ−Ｚｎ共析系合金を溶解鋳造し、これを２８０〜４１０℃の温度で３０分〜３時間保持した後、−４〜２０℃の水中で急冷した鋳塊を更に１５０〜２７０℃の温度範囲において厚さ０．１〜１ｍｍの帯状に圧延加工して製造されることを特徴とするＺｎ−Ａｌ共析系合金接合材の製造方法。 An alloy bonding material for bonding a semiconductor substrate to a ceramic substrate or a metal substrate, the alloy bonding material being 17-30 mass % Al-0-1.5 mass % Cu-0-0.5 mass % Mg -Zinc eutectoid alloy was melt cast and held at a temperature of 280 to 410 ° C for 30 minutes to 3 hours, and then the ingot rapidly cooled in water at -4 to 20 ° C was further in a temperature range of 150 to 270 ° C. A method for producing a Zn-Al eutectoid alloy bonding material, which is produced by rolling into a strip having a thickness of 0.1 to 1 mm. 半導体基体とセラミック基板もしくは金属基板との間に１７〜３０質量％Ａｌ−０〜１．５質量％Ｃｕ−０〜０．５質量％Ｍｇ−Ｚｎ系からなるＺｎ−Ａｌ共析系合金接合材を介在し、該接合材を２８０〜４１０℃に加熱し、超塑性を発現する状態で１〜３０分間保持した後徐冷することを特徴とする接合方法。 Zn-Al eutectoid alloy bonding material composed of 17-30 mass % Al-0-1.5 mass % Cu-0-0.5 mass % Mg-Zn system between the semiconductor substrate and the ceramic substrate or metal substrate The joining method is characterized in that the joining material is heated to 280 to 410 ° C., held for 1 to 30 minutes in a state of developing superplasticity, and then gradually cooled. 半導体基体とセラミック基板もしくは金属基板との間に１７〜３０質量％Ａｌ−０〜１．５質量％Ｃｕ−０〜０．５質量％Ｍｇ−Ｚｎ系からなるＺｎ−Ａｌ共析系合金接合材を介在し、該接合材を２００〜２７５℃に加熱し、超塑性を発現する状態で１〜３０分間保持した後、２８０〜４１０℃に昇温後徐冷することを特徴とする接合方法。 Zn-Al eutectoid alloy bonding material composed of 17-30 mass % Al-0-1.5 mass % Cu-0-0.5 mass % Mg-Zn system between the semiconductor substrate and the ceramic substrate or metal substrate The joining method is characterized in that the joining material is heated to 200 to 275 ° C., held for 1 to 30 minutes in a state of developing superplasticity, then heated to 280 to 410 ° C. and then gradually cooled. 半導体基体、半導体基体に直接またはセラミック基板を介して接合層によって接合された金属基板を備え、接合層が１７〜３０質量％Ａｌ−０〜１．５質量％Ｃｕ−０〜０．５質量％Ｍｇ−Ｚｎ系からなるＺｎ−Ａｌ共析系合金接合材からなり、接合時に超塑性現象を発現し、接合後は超塑性を発現しない金属組織を有することを特徴とする半導体装置。 A semiconductor substrate, and a metal substrate bonded to the semiconductor substrate directly or via a ceramic substrate by a bonding layer, the bonding layer being 17 to 30% by mass Al-0 to 1.5% by mass Cu-0 to 0.5% by mass A semiconductor device comprising a Zn-Al eutectoid alloy bonding material made of Mg-Zn and having a metal structure that exhibits a superplastic phenomenon during bonding and does not exhibit superplasticity after bonding. 前記半導体基体が炭化珪素であることを特徴とする請求項５項記載の半導体装置。   6. The semiconductor device according to claim 5, wherein the semiconductor substrate is silicon carbide.
JP2007285825A 2007-11-02 2007-11-02 Zn-Al eutectoid alloy bonding material, method for producing Zn-Al eutectoid alloy bonding material, bonding method using Zn-Al eutectoid alloy bonding material, and Zn-Al eutectoid alloy bonding material Semiconductor device Active JP4803834B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2007285825A JP4803834B2 (en) 2007-11-02 2007-11-02 Zn-Al eutectoid alloy bonding material, method for producing Zn-Al eutectoid alloy bonding material, bonding method using Zn-Al eutectoid alloy bonding material, and Zn-Al eutectoid alloy bonding material Semiconductor device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2007285825A JP4803834B2 (en) 2007-11-02 2007-11-02 Zn-Al eutectoid alloy bonding material, method for producing Zn-Al eutectoid alloy bonding material, bonding method using Zn-Al eutectoid alloy bonding material, and Zn-Al eutectoid alloy bonding material Semiconductor device

Publications (2)

Publication Number Publication Date
JP2009113050A JP2009113050A (en) 2009-05-28
JP4803834B2 true JP4803834B2 (en) 2011-10-26

Family

ID=40780776

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2007285825A Active JP4803834B2 (en) 2007-11-02 2007-11-02 Zn-Al eutectoid alloy bonding material, method for producing Zn-Al eutectoid alloy bonding material, bonding method using Zn-Al eutectoid alloy bonding material, and Zn-Al eutectoid alloy bonding material Semiconductor device

Country Status (1)

Country Link
JP (1) JP4803834B2 (en)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5675525B2 (en) * 2011-07-28 2015-02-25 日産自動車株式会社 Semiconductor device manufacturing method and semiconductor device
JP6016095B2 (en) * 2011-09-22 2016-10-26 日産自動車株式会社 Joining method and joining parts
JP6003108B2 (en) 2011-09-22 2016-10-05 日産自動車株式会社 Joining method and joining part manufacturing method
WO2016052700A1 (en) * 2014-10-02 2016-04-07 国立大学法人茨城大学 Bonding layer structure using alloy bonding material, forming method for same, semiconductor device having said bonding layer structure, and method for manufacturing same
JP6590336B2 (en) * 2015-06-03 2019-10-16 国立大学法人茨城大学 High heat-resistant solder junction semiconductor device and manufacturing method thereof
JP6732189B2 (en) * 2016-10-21 2020-07-29 国立研究開発法人産業技術総合研究所 Semiconductor device and manufacturing method thereof
CN107739870A (en) * 2017-09-11 2018-02-27 北方民族大学 A kind of preparation method of SiC reinforcement high Al-Zn base composite
US20230054798A1 (en) * 2020-03-27 2023-02-23 Mitsubishi Electric Corporation Metal jointed body, semiconductor device, wave guide tube, and method for joining members to be joined

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5245567A (en) * 1975-10-09 1977-04-11 Mitsubishi Heavy Ind Ltd Metal diffusion welding method using superplastic material
JPH0288735A (en) * 1988-09-26 1990-03-28 Toyota Central Res & Dev Lab Inc Composite material combining ductility and wear resistance, its manufacture and its application
JPH04210448A (en) * 1990-11-30 1992-07-31 Agency Of Ind Science & Technol Functionally gradient material using zn-22al superplastic powder and method for forming the same
JPH09312295A (en) * 1996-03-21 1997-12-02 Matsushita Electric Ind Co Ltd Bump forming body and forming method of bump
JP3674897B2 (en) * 1998-02-06 2005-07-27 株式会社神戸製鋼所 Zn-Al alloy for vibration control and manufacturing method thereof
JP3936165B2 (en) * 2001-10-23 2007-06-27 株式会社神戸製鋼所 Bolt friction joining method and filler material for bolt friction joining

Also Published As

Publication number Publication date
JP2009113050A (en) 2009-05-28

Similar Documents

Publication Publication Date Title
JP4803834B2 (en) Zn-Al eutectoid alloy bonding material, method for producing Zn-Al eutectoid alloy bonding material, bonding method using Zn-Al eutectoid alloy bonding material, and Zn-Al eutectoid alloy bonding material Semiconductor device
Mokhtari A review: Formation of voids in solder joint during the transient liquid phase bonding process-Causes and solutions
US8592986B2 (en) High melting point soldering layer alloyed by transient liquid phase and fabrication method for the same, and semiconductor device
TWI655296B (en) Highly reliable lead-free solder alloy, its use and method of forming solder joints
JP2008311383A (en) Bonding wire, bonding method using the same, and semiconductor device as well as joint construction
US20210407953A1 (en) Solder material for semiconductor device
JP5186719B2 (en) Ceramic wiring board, manufacturing method thereof, and semiconductor module
JP2019520985A6 (en) Highly reliable lead-free solder alloy
JP2011124585A (en) Ceramic wiring board and manufacturing method and semiconductor module of the same
JP4699822B2 (en) Manufacturing method of semiconductor module
JP2009147111A (en) Bonding material, method of manufacturing the same, and semiconductor apparatus
US9070561B2 (en) Semiconductor device and die bonding structure thereof
CN109641323B (en) Soft soldering material
JP6429208B2 (en) Semiconductor device and moving body
CN107431051A (en) Manufacture method with gelled power module substrate
CN112823073B (en) Joined body, insulated circuit board with heat sink, and heat sink
JP4592486B2 (en) Semiconductor module
JP4057436B2 (en) Copper base alloy and heat sink material using the copper base alloy
JP6579551B2 (en) Bonding layer structure using alloy bonding material and method for forming the same, semiconductor device having the bonding layer structure, and method for manufacturing the same
Chen et al. Dissimilar Joining of Pure Aluminum to SiC p/Al-MMCs Using an AlMgGaLi Active Interlayer Foil
JP2017147285A (en) CONJUGATE JOINED BY CLAD MATERIAL OF Pb-free Zn-Al-based ALLOY SOLDER AND METAL BASE MATERIAL
CN100362655C (en) Thermal interface materials, and compositions comprising indium and zinc
Ang et al. Packaging of high-temperature power semiconductor modules
Zhang et al. Perspectives of High-Temperature Pb-Free Bonding Materials
JP2017001049A (en) Joint layer structure and joint method by alloy joint material, semiconductor device and manufacturing method thereof

Legal Events

Date Code Title Description
A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20100402

A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20101101

A871 Explanation of circumstances concerning accelerated examination

Free format text: JAPANESE INTERMEDIATE CODE: A871

Effective date: 20101101

A975 Report on accelerated examination

Free format text: JAPANESE INTERMEDIATE CODE: A971005

Effective date: 20101124

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20101227

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20110223

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20110413

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20110530

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20110802

A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20110808

R150 Certificate of patent or registration of utility model

Ref document number: 4803834

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150

Free format text: JAPANESE INTERMEDIATE CODE: R150

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20140819

Year of fee payment: 3

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250