| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve a problem that there is a possibility of the crack of a solder layer and the damage of a semiconductor element caused by temperature cycle or stress applied to the solder layer and the semiconductor element, in a semiconductor device in which the semiconductor element is adhered to a base board composed of metal with a solder layer. <P>SOLUTION: The semiconductor device is equipped with a square thermal diffusion board 2 adhered to a base board 1 through a first solder layer 3a, and a square semiconductor element 4 adhered to the thermal diffusion board 2 through a second solder layer 3b. The thermal diffusion board 2 is chamfered at its four corners, the length of the diagonal line thereof is made to be the shape smaller than that of the semiconductor element 4 by which the first solder layer 3a and the second solder layer 3b are connected in four corners, and the thickness of the corresponding solder layers only is made thicker. Consequently, the thermal stress caused by the temperature cycle is made to be easily absorbed by the solder layers of four corners without sacrificing the electrical property and the heat dissipation property. <P>COPYRIGHT: (C)2007,JPO&INPIT |
