Patent ID: 8785923

Claim:
A semiconductor device comprising: a first transistor and a second transistor overlapping with each other, wherein the first transistor comprises: a semiconductor substrate comprising a source region, a drain region and a groove portion between the source region and the drain region; a first gate insulating film formed along a shape of the groove portion; and a gate electrode formed in the groove portion with the first gate insulating film interposed therebetween, wherein the second transistor comprises: the gate electrode formed in the groove portion; a second gate insulating film covering the gate electrode; a semiconductor film overlapping with the gate electrode with the second gate insulating film interposed therebetween; and a pair of electrodes formed in contact with the semiconductor film, wherein each of the pair of electrodes is a metal layer, and wherein one of the source region and the drain region is electrically connected to one of the pair of electrodes.