| 摘要 |
In a power module according to the present invention, a copper layer composed of copper or a copper alloy is provided at a surface of a circuit layer (12) onto which a semiconductor element (3) is bonded, and a solder layer (20) formed by using a solder material is formed between the circuit layer (12) and the semiconductor element (3). An alloy layer (21) containing Sn as a main component, 0.5% by mass or more and 10% by mass or less of Ni, and 30% by mass or more and 40% by mass or less of Cu is formed at the interface between the solder layer (20) and the circuit layer (12), the thickness of the alloy layer (21) is set to be within a range of 2 µm or more and 20 µm or less, and a thermal resistance increase rate is less than 10% after loading a power cycles 100,000 times under a condition where an energization time is 5 seconds and a temperature difference is 80°C in a power cycle test. |
