| 摘要 |
PURPOSE:To reduce the fatigue of solder, by soldering stress buffer metal to the rear surface of a semiconductor chip, and soldering an electrode having stress buffering characteristic to the surface of the semiconductor chip. CONSTITUTION:An electrode 6 has a linear expansion coefficient close to that of a semiconductor chip 1 and consists of a material such as Ni-Fe alloy having excellent machinability. The electrode 6 is soldered to the surface of the semiconductor chip 1. The electrode 6 has a stress buffering characteristic. As a stress buffering metal 4, molybdenum, Ni-Fe alloy and the like are used. When a current supply to a semiconductor element is repeated, the current intermittently flows through the electrode 6, the semiconductor 1 and the stress buffering metal 4. The temperature of the semiconductor element is repeatedly increased and decreased. Each part is repeatedly expanded and contracted. Accordingly, solder connecting the parts is fatigued. Since the linear expansion coefficients of the semiconductor chip 1, the stress buffering metal 4 and the electrode have the close values, the semiconductor element is intermittently energized. Even if the temperature is increased and decreased, the degree of the solder fatigue becomes less than a conventional element.
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