Patent ID: 7142451

Claim:
A method of operating a nonvolatile semiconductor memory apparatus, comprising a first conductive type semiconductor substrate (SUB, W), a first conductive type channel forming region (CH) with a high concentration channel region HR contacting a sub bit line SBL, and regulated in a surface region of said semiconductor substrate (SUB, W), a first source/drain region (S, SSL) formed on one side of said channel forming region (CH) on a surface region of said semiconductor substrate (SUB, W), a second source/drain region (D, SBL) formed on the other side of said channel forming region in the surface region (CH) of said semiconductor substrate (SUB, W), a charge storage film (GD) having a charge storage faculty formed at least on said channel forming region (CH), and a gate electrode (WL) formed on said charge storage film, said charge storage film (GD) having a lower layer (BTM) with a film thickness on the order of 2.5 nm to 6.0 nm, a main charge storage film (CHS), and a second dielectric film (TOP) having a thickness of at least 3.5 nm, including the steps of: generating a first voltage (Vd) and second voltage (Vg−Vgwell), applying said generated first voltage (Vd) to said second source/drain region (D, SBL) by using potential of said first source/drain region (S, SSL) as a reference, applying said generated second voltage (Vg−Vgwell) to said gate electrode (WL), generating hot electrons (HE) by ionization collision on said second source/drain region (D, SBL) side, and injecting said generated hot electrons (HE) to said charge storage film (GD) from said second source/drain region (D, SBL) side at the time of writing data; and generating a third voltage (Vd−Vg), applying said generated third voltage (Vd−Vg) to between said second source/drain region (D, SBL) and said gate electrode (WL), generating hot holes (HH) on said second source/drain region (D, SBL) side, and injecting said generated hot holes (HH) to an injection region for said hot electrons (HE) of said charge storage film (GD) at the time of erasing data.