| 摘要 |
PURPOSE:To increase the reliability of a face down type semiconductor device by providing a radiation shielding plate on an insulating substrate. CONSTITUTION:A highly pure Si thin plate 6 whose thickness is about 30mum is bonded on an alumina substrate 1 so as to cover the surface which faces an active region 5 of a semiconductor element 3 other than solder bump parts 4. The bumps 4 are contacted to electrodes 2 on said substrate 1, and compressed, heated, and bonded. Since the distance of intrusion of standard alpha-rays having energy of 5Mev into Si is about 25mum, the thin plate 6 sufficiently shields the alpha-rays, and prevents the occurrence of software errors. The alpha-rays from alumina around the shielding plate 6 has a very small incident angle with respect to the surface of the element 3, and does not reach the surface, or only very small amount of energy reaches the surface. In this simple constitution, the reliability of the device is greatly enhanced. |
