The present invention relates to a semiconductor device that contains a trench metal-insulator-metal capacitor and a field effect transistor. The DRAM includes a memory cell, a bit line associated with the memory cell, a local buffer, and a bit line sense amplifier. A gate electrode 14 whose both side walls have a shape roughly perpendicular to the SOI substrate is formed via a gate insulating film on the channel region 19. The developing unit develops the electrostatic latent image into a toner image.