A plurality of mesas are formed in the substrate. Each pair of mesas forms
a trench. A plurality of diffusion areas are formed in the substrate. A
mesa diffusion area is formed in each mesa top and a trench diffusion
area is formed under each trench. A vertical, non-volatile memory cell is
formed on each sidewall of the trench. Each memory cell is comprised of a
fixed threshold element located vertically between a pair of non-volatile
gate insulator stacks. In one embodiment, each gate insulator stack is
comprised of a tunnel insulator formed over the sidewall, a deep trapping
layer, and a charge blocking layer. In another embodiment, an injector
silicon rich nitride layer is formed between the deep trapping layer and
the charge blocking layer.