Semiconductor memory device for dynamically storing data with channel body of transistor used as storage node

Abstract

A semiconductor memory device includes a plurality of MIS transistors arranged at intersections of first word lines and bit lines formed on an SOI substrate and each configuring a memory cell. Each of the plurality of MIS transistors includes a channel body formed in a semiconductor layer on an insulating film and set in an electrically floating state, a first extension region formed in contact with the channel body in the semiconductor layer and arranged in a first word line direction, a gate insulating film formed on the channel body, a gate electrode formed on the gate insulating film and electrically connected to a corresponding one of the first word lines, and source and drain regions separately formed in a bit line direction in the semiconductor layer to sandwich the channel body.