Improved performance of GeON as charge storage layer in flash memory by optimal annealing

摘要

We have fabricated the Al/Al_2O_3/GeON/SiO_2/Si charge-trapping flash memory with different annealing temperatures for the GeON charge storage layer. The physical structure of memory device was studied by transmission electron microscopy and the chemical composition of the GeON film was investigated by X-ray photoelectron spectroscopy. The proposed device that had been annealed at 600 ℃ exhibited a large 5.75-V initial memory window, a 3.77-V 10-year extrapolated retention window, a 6.08-V endurance window at 105 cycles under very fast (100-μs) and low-voltage (±16-V) program/erase. The excellent properties are due to charge traps with desirable energy levels generated by optimal annealing, indicating that GeON is a potential candidate as the charge storage layer for flash memory applications.