Patent 11094648 was granted and assigned to Denka (company) on August, 2021 by the United States Patent and Trademark Office.
A power module includes a base plate, a ceramic insulating substrate bonded on the base plate, and a semiconductor element bonded on the ceramic insulating substrate, wherein a surface of the base plate on a side opposite to the ceramic insulating substrate has a warp with a convex shape, and a linear thermal expansion coefficient α1 (×10−6/K) of the base plate and a linear thermal expansion coefficient α2 (×10−6/K) of the ceramic insulating substrate when a temperature decreases in the range of 25° C. to 150° C. satisfy the following Expression (1).