Patent ID: 7447082

Claim:
A method for programming a single-poly non-volatile memory unit, said single-poly non-volatile memory unit comprising an ion well of a first conductivity type, a source doping region of a second conductivity type, a drain doping region of said second conductivity type and a channel region between said source doping region and said drain doping region, wherein said channel region is divided into a first channel region and a second channel region connected to said first channel region with the same polarity, and said first channel region has a threshold voltage (Vth), a gate dielectric layer disposed directly above said first channel region, a control gate stacked on said gate dielectric layer, a dielectric spacer on a sidewall of said control gate and directly above said second channel region, wherein said dielectric spacer comprises a charge trapping dielectric medium; and an asymmetric lightly doped drain (LDD) region of said second conductivity type disposed merely between said control gate and said source doping region, said method comprising: connecting said ion well to a well voltage (VB); electrically connecting said drain doping region to a drain voltage (VD) to form a reverse bias at a junction between said drain doping region and said ion well; electrically connecting said source doping region to a source voltage (VS); and electrically connecting said control gate to a gate voltage (VG) to render said first channel in an open and strong inversion state, wherein carriers are drawn into said first channel from said source doping region to generate channel hot electrons (CHEs), and more hot electrons are generated due to ion impact ionization and said hot electrons are re-directed, injected and trapped in said charge trapping dielectric medium due to a vertical electric field generated by said gate voltage (VG).