The extraction of two-dimensional MOS transistor doping via inverse modeling

Abstract

We present a novel method for the determination of the two-dimensional (2D) doping profile of a MOSFET using inverse modeling. In our method, the logarithms of the donors and accepters concentrations are each represented by a tensor product spline (TPS). The TPS coefficients are extracted by nonlinear, least squares optimization from source/drain (S/D) diode and gate capacitance data. After validating the method by applying it to simulated capacitance data, we present the results of using the new technique to extract the 2D profile of a 0.42 μm gate length CMOS technology N-channel device.