Abstract
A single side non-volatile memory cell on unit device and method of operating the same are disclosed. The device is formed in the n-well and compatible with CMOS processes comprises a selecting gate, two ONO spacers, a p+ source/drain, a p-extended source, and an n-extended drain. To program the cells, two strategies can be taken. One is by a band to band hot electron injection. The other is by channel hot hole induced hot electron injection. To read the nonvolatile cells, a reverse read is taken. In the reading process, the biased on the selecting gate form a tapered channel whose narrow end connects the accumulation channel in the extended source electrode. While the cell has electrons in the nitride layer, a channel is formed thereunder so that a hole current can be read out. To erase the datum in the selected cell, two approaching can be carried out. One is by FN (Fowler_Nordheim) erase, the other is by band to band induced hot hole injection.