| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To solve the problem that break occurs at a low melting point solder material for connecting a connection pad of a wiring board with an external electric circuit, and thereby the connection reliability of a semiconductor element to the external electric circuit is deteriorated. <P>SOLUTION: This wiring board 4 is constituted of a square insulating base substance 1 which is composed of an electric insulating material and has a semiconductor element mounting part on its surface, a large number of connection pads 6 formed on a lower surface of the insulating base substance 1, and a plurality of wiring conductors 2 led from the mounting part of the insulating base substance 1 to the connection pads 6. An auxiliary pad 9 is formed at the corner the lower surface of the insulating base substance 1, the height of the outer edge of the auxiliary pad 9 is made smaller than that of a central part, and the surface roughness of the outer edge of the auxiliary pad 9 is made at least 1.5μm in arithmetical mean roughness (Ra). <P>COPYRIGHT: (C)2004,JPO</p> |
