Abstract: A memory cell includes an N-type well, three P-type doped regions formed on the N-type well, a dielectric layer formed on the N-type well and between a first doped region and a second doped region of the three P-type doped regions, a first gate formed on the dielectric layer, a charge storage structure formed on the N-type well and between the second doped region and a third doped region of the three P-type doped regions, and a second gate formed on the charge storage structure. Data is stored in the memory cell by injecting electrons based on the channel-hot-hole induced hot-electron injection mechanism, the band-to-band tunneling induced electron injection mechanism and the Fowler-Nordheim tunneling mechanism. Data is erased from the memory cell by ejecting electrons based on the Fowler-Nordheim tunneling mechanism. Whether data is stored in the charge storage structure or not can be distinguished by read operation.