Surface Potential Equation for Metal-Oxide-Semiconductor Capacitors Considering the Degenerate Effect

A surface potential equation (SPE) considering the degenerate effect is derived. To make the degenerate SPE analysis, an empirical approximation for the Fermi integral is applied in the derivation. Dependences of surface potential and square of electric field on gate voltage calculated from the degenerate and non-degenerate models are compared with great discrepancy. Further, theoretical C–V relationships are compared with the experimental data for two structures and it is shown that the degenerate SPE−based C_g–V_g matches with the experimental data much better than the non-degenerate one, which confirms that the degenerate effect is inevitable for surface potential-based metal-oxide-semiconductor device modeling.