Semiconductor device and driving method therefor

A driving method for a semiconductor device which includes a bulk semiconductor substrate and a plurality of storage elements formed on said bulk semiconductor substrate and each including a thyristor formed on said bulk semiconductor substrate and including a first region of a first conductor type, a second region of a second conduction type opposite to the first conduction type, a third region of the first conduction type and a fourth region of the second conduction type jointed together in order, a gate electrode formed on the third region, and a field effect transistor formed on said semiconductor substrate on which said thyristor is formed and connected to said fourth region of said thyristor, comprising the steps of:

• a bit line being connected to the cathode of said field effect transistor;
• applying, upon turning off operation of a selected one of said storage elements, a first voltage to the first region side of said thyristor of the selected storage element while a second voltage higher than the first voltage is applied to the cathode side of said field effect transistor of the selected storage element;
• and
• applying a voltage lower than the first voltage to a word line formed for said field effect transistor of a non-selected one of the storage elements connected to the bit line connected to the selected storage element.