| 摘要 |
<p>PURPOSE:To remove defective writing resulting from the floating effect of a memory cell not selected by applying potential having polarity stopping the formation of an inversion layer to a Si substrate under a gate insulating film in an IGFET. CONSTITUTION:An array is formed by an IGFET memory cells in nXm numbers. When a word line Xn' is selected and high positive potential VCG is applied, a digit line Ym' is selected and high positive potential VD is applid and -VS is applied to a terminal Z, high currents flow through the channel of the cell Tm'n', and writing is conducted. In this case, floating gate potential VF floats at drain potential VD by capacitance among each region and a floating gate even when a control gate is grounded in other cells on the line Ym', but is low inhibited by reverse bias -VS. Since the threshold potential VTO of a channel viewed from the floating gate is increased by -VS, currents do not flow through the memory cell not selected on the digit line selected, and VD causing defective writing is not dropped.</p> |
