The effect of trench-gate-oxide structure on EPROM device operation

A floating-gate erasable programmable read-only memory (EPROM) cell with a thin trench-gate-oxide (TGO) structure near the drain region was fabricated using electron-beam lithography technology. Several promising advantages were found for the TGO cell. The writing time was measured to be 100 faster than conventional devices of the same dimensions. Two-dimensional (2-D) simulation of the TGO structure indicated that longitudinal and transverse channel electric fields are generated which simultaneously increase the hot-electron population in the channel and the injection efficiency into the floating gate. The devices exhibit high-transconductance, fast programming, good-tolerance to unintentional writing during readout, and potential for flash-erase application.<
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