Performance evaluation of field-enhanced P-channel split-gate flash memory

A p-channel split-gate Flash memory cell, employing a field-enhanced structure, is investigated in this letter. A cell with a sharp poly-tip structure is utilized to enhance the electric field, while using Fowler-Nordheim tunneling through the interpoly oxide. The cell demonstrated an erase voltage as low as 12 V. In cell programming, both channel-hot-hole impact ionization induced channel-hot-electrons (CHE) and band-to-band tunneling induced hot electrons (BBHE) are evaluated. BBHE shows an injection efficiency of /spl sim/2 orders in magnitude higher than that of CHE. The cell also demonstrated an acceptable program disturb window, which is of high concern in a p-channel stacked-gate cell. Both programming approaches can pass 300 k program/erase cycles.