Feasibility of SIO2/Al2O3 tunnel dielectric for future Flash memories generations

In this paper, we investigate the feasibility of SiO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> stack tunnel dielectric for future Flash memory generations using statistical leakage current simulations. We show that the statistical Monte Carlo (MC) simulator we employed reproduces accurately leakage currents measured on SiO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> dielectric capacitors. Exploiting its statistical capabilities, we calculate leakage current distributions in Flash memory retention conditions. We show that the high defectiveness of AI<sub>2</sub>O<sub>3</sub> stacks strongly reduces the potential improvement of Flash retention due to the introduction of AI<sub>2</sub>O<sub>3</sub> tunnel dielectric.

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