SEMICONDUCTOR DEVICE

PROBLEM TO BE SOLVED: To provide a semiconductor device capable of suppressing stress to a semiconductor element.SOLUTION: A semiconductor device element 20 is bonded on a lower electrode 30 through a bonding material 50, and on the semiconductor element 20, an upper electrode 40 is bonded through a bonding material 60. A bonding area between the semiconductor element 20 and the upper electrode 40 is smaller than a bonding area between the semiconductor element 20 and the lower electrode 30. Further, the linear expansion coefficient of the upper electrode 40 is larger than the linear expansion coefficient of the lower electrode 30. The upper electrode 40 has a linear expansion coefficient to cancel a warp vertically produced on the semiconductor element 20 by stress generated by a difference of the linear expansion coefficients between the semiconductor element 20 and the upper electrode 40 and a difference of the linear expansion coefficients between the semiconductor element 20 and the lower electrode 30.