In a two-transistor gain cell structure, a semiconductor memory device
capable of stable reading without malfunction and having small-area
memory cells is provided. In a two-transistor gain cell memory having a
write transistor and a read transistor, a write word line, a read word
line, a write bit line, and a read bit line are separately provided, and
voltages to be applied are independently set. Furthermore, a memory cell
is connected to the same read word line and write bit line as those of an
adjacent memory cell.