Patent ID: 8288868
Filing Date: 2012-10-16
Classification: B23K,H01L

Abstract:
1. A semiconductor device comprising: a first substrate; an operation layer made of semiconductor, the operation layer being bonded to the first substrate; and a bonding layer made of alloy containing Au, Sn, and another third element, the bonding layer bonding the operation layer to the first substrate; wherein a central region, a first region disposed between the central region and the first substrate, and a second region disposed between the central region and the operation layer are defined in the bonding layer; and wherein relative proportions of elements in the bonding layer are such that a relative proportion of Sn in the central region is smaller than that in either of the first and second regions, a relative proportion of Au in the central region is larger than that in either of the first and second regions, and a relative proportion of the third element in the central region is smaller than that in either of the first and second regions.