Patent 7535097 was granted and assigned to Olympus Group on May, 2009 by the United States Patent and Trademark Office.
A semiconductor device includes a semiconductor chip having at least an electrode pad and a device formed on a semiconductor layer on its surface, a seal cap having a recess portion facing the device which is adhered to the surface of the semiconductor chip, and a cavity as an airspace formed by the recess portion between the semiconductor chip and the seal cap. The semiconductor chip includes a stepped portion at a portion of the back surface opposite the surface to have an uneven thickness.