Effect of Image Force on Tunneling Current for Ultra Thin Oxide Layer Based Metal Oxide Semiconductor Devices

In this letter, an analytical model for evaluation of tunneling current density of ultra thin Metal Oxide Semiconductor (MOS) devices is presented. For such devices, the area of the potential barrier is reduced by rounding off the corners, reducing the thickness due to image potential, hence are very important for accurate modeling. In this work, improvement in the analysis is brought in by taking into account the barrier height lowering due to the image force effect. The voltage range under consideration is 0 ≤ V ≤ ψ₁/e. Tunnel resistivity is also evaluated utilizing this tunneling current density model. Theoretical predictions are compared with the results obtained by the 2D numerical device simulator ATLAS and published experimental results, excellent agreements between the three are observed.