Patent ID: 7515479

Claim:
A method for programming bit data to a nonvolatile semiconductor memory device, said nonvolatile semiconductor memory device comprising, an n type well formed in a semiconductor substrate, a source and a drain of p+ regions formed in the surface of said n type well with a predetermined interval, a channel region formed between said source and said drain, a charge accumulation layer of a floating gate, a nano-crystal layer, a nonconductive charge trap layer formed above said channel region via a tunnel insulating layer, and a gate electrode formed above said charge accumulation layer via an insulating layer, said method comprising: applying Vg, Vsub, Vs and Vd to the gate electrode, the n type well, the source and the drain respectively during programming, the Vg, the Vsub, the Vs and the Vd being in a relationship of “Vg>Vsub>Vs>Vd” and “Vg−Vd” being not less than an electrical potential difference necessary to generate a band to band tunneling current at said channel region, thereby generating hot electrons near the drain by band to band tunneling; and injecting said hot electrons into said charge accumulation layer to program the bit data.