The gate tunnel leakage current is increased in the up-to-date process, so that
it is necessary to reduce the gate tunnel leakage current in the LSI which is driven
by a battery for use in a cellular phone and which needs to be in a standby mode
at a low leakage current. In a semiconductor integrated circuit device, the ground
source electrode lines of logic and memory circuits are kept at a ground potential
in an active mode, and are kept at a voltage higher than the ground potential in
an unselected standby mode. The gate tunnel leakage current can be reduced without
destroying data.