Gate tunneling current in thin oxide MOSFET

Quantum mechanical tunneling of electrical conduction in a thin insulating film (SiO₂) from the strongly inverted Si surface has been studied. A simple method of calculating the penetration probability of the energetic electrons, and the tunneling current is proposed. These electrons are from a series of quantized energy levels in the potential well (assuming triangular nature), formed by the large bending of the silicon conduction band at the surface. Due to the down scaling of device dimensions, the field across the oxide becomes high enough, and causes a large band bending in the form of a narrow potential well. The gate oxide thickness and gate voltage dependence of the tunneling current are analyzed using the tunneling current model. This study may be helpful in predicting the oxide breakdown process