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 (Al ₂ O ₃ ) gate dielectric layer on the Si substrate. Electron/hole blocking mechanism was archived by controlling the Al ₂ O ₃ composition, band gap and post deposition annealing affect, respectively. The chemical composition of the Al ₂ O ₃ was confirmed from the X-ray photoelectron spectroscopy analysis. The capacitance-voltage (C-V) characteristic of Al/Al ₂ O ₃ /Si (MOS) metal-oxide-semiconductor structure showed clear accumulation, depletion and inversion regions as-compared with the Al/SiN _x /Si MOS devices, respectively, From the C-V curves, the flat band voltage(Δ _FB ) was shifted accordingly positive and negative with respect to electron/hole trapping effect. In addition, 10 nm AlO _x storage layer and SiN _x storage layer were compared in the same structure. The 10 nm SiN _x 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.