Current vs Substrate Bias Characteristics of MOSFETs as a Tool for Parameter Extraction

An application of the drain current vs substrate bias characteristics of MOSFETs for the device parameter extraction is presented. Modeling of the substrate bias effect on the MOSFET drain current is briefly discussed. A method of the MOSFET characterization is formulated. It requires a measurement of two I(V) characteristics, including the I _D (V _BS ) smooth curve measured in a "sweep" mode. The method allows to extract the threshold voltage parameters and to estimate the in-depth doping profile in the substrate. The proposed approach is demonstrated using I(V) data of the MOSFETs manufactured in ITE in a bulk CMOS process.