A method of operating a memory cell by applying a positive voltage to the
gate sufficient to cause hole tunneling from the gate toward the charge
storage layer is disclosed. The method is applied to a memory cell
including a semiconductor layer having at least two source/drain regions
disposed below a surface of the semiconductor layer and separated by a
channel region. The memory cell also has a lower insulating layer
disposed above the channel region; a charge storage layer disposed above
the lower insulating layer; an upper insulating multi-layer structure
disposed above the charge storage layer. The upper insulating multi-layer
structure comprises a lower dielectric layer and an upper nitride layer
disposed above the lower dielectric layer and the memory cell has a gate
disposed above the upper insulating multi-layer structure.