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The forward gated-diode method is used in this paper to extract the dielectric oxide thickness and body doping concentration of nano-scale MOSFETs, especially when both of the variables are unknown previously. Firstly the dielectric oxide thickness and the body doping concentration as a function of forward gated-diode peak recombination-generation (R-G) current is derived from the device physics. And then the peak R-G current characteristics of the MOSFETs with different dielectric oxide thicknesses and body doping concentrations are simulated with ISE-Dessis for parameter extraction. The results from the simulation data demonstrate an excellent agreement with those extracted from the forward gated-diode method.

An explicit surface potential model of the bulk-MOSFET with inclusion of the poly-gate accumulation, depletion, and inversion effects is derived from the basic MOS device physics and its solution result is also discussed in this paper. By the means of the appropriate approximations and device physics derivation, the complex group of the surface-potential and poly-silicon potential equations is transformed into one single explicit surface potential equation of a MOSFET with the poly-silicon accumulation/depletion/inversion effects. It is demonstrated that the proposed surface potential equation and its solution correctly yet accurately describe the physical behaviors of the poly-silicon potential, surface potential, gate charge, the gate capacitance, with continuous and smooth transitions from the accumulation region, thorough the depletion region, finally to the strong inversion region. The predicted MOSFET trans-capacitance behavior is verified by the result of fully numerical iteration method, thus, the surface potential equation presented can be used in advanced surface potential based MOSFET compact model development.