A study on Improvement of Electrical and Retention characteristics of Non-volatile Memory with Al2O3 Insulator

We report the controllable charge (Electron/hole) trapping window layer properties of atomic layer deposited (ALD) aluminum oxide (Al2O3) gate dielectric layer on the Si substrate. Electron/hole blocking mechanism was archived by controlling the Al2O3 composition, band gap and post deposition annealing affect, respectively. The chemical composition of the Al2O3 was confirmed from the X-ray photoelectron spectroscopy analysis. The capacitance-voltage (C-V) characteristic of Al/Al2O3/Si (MOS) metal-oxide-semiconductor structure showed clear accumulation, depletion and inversion regions as-compared with the Al/SiNx/Si MOS devices, respectively, From the C-V curves, the flat band voltage(ΔFB) was shifted accordingly positive and negative with respect to electron/hole trapping effect. In addition, 10 nm AlOx storage layer and SiNx storage layer were compared in the same structure. The 10 nm SiNx storage layer showed a very low retention of 55.1% and the memory window also showed a relatively low value of 2.72V at 18V.