Semiconductor device with back surface electrode including a stress relaxation film

摘要

A semiconductor device includes a semiconductor substrate which has first and second principal surface regions; an insulated gate structure which is formed in the first principal surface region; a back surface region semiconductor layer which is formed in the second principal surface region and has a thickness of at most 5 mum; an outermost metal film; and a back surface electrode which is formed in the second principal surface region between the back surface region semiconductor layer and the outermost metal film and which is composed of a plurality of films which are laminated and include a stress relaxation film so that false judgment of chip quality based on leakage current measurements during manufacturing is reduced particularly when dust is present and skews leakage current measurements due to strain on the wafer and the piezoelectric effect produced.