Patent Number: 7,102,228

Title: Semiconductor device

Abstract: A semiconductor device comprising a substrate, a semiconductor element mounted on the substrate, an inner annular stiffener provided on the substrate in an outer side of the semiconductor element, and an outer annular stiffener provided on the substrate in an outer side of the inner annular stiffener. The inner annular stiffener and the outer annular stiffener are made of different materials. Particularly, the thermal expansion coefficient of the inner annular stiffener is selected to be smaller than that of the substrate, and the thermal expansion coefficient of the outer annular stiffener is selected to be larger than that of the substrate. The amount of deformation of the substrate is thus decreased.

Inventors: Kanda; Takashi (Kawasaki, JP)

Assignee: Fujitsu Limited

International Classification: H01L 23/06 (20060101); H01L 23/12 (20060101); H01L 23/04 (20060101)

Expiration Date: 9/05/02018