Error-Free Matthiessen´s Rule in the MOSFET Universal Mobility Region

Through the experimentally validated inversion-layer mobility simulation, we devise an error-free version of Matthiessen´s rule for a single-gate n-channel bulk MOSFET in the universal mobility region. The core of the new rule lies in a semi-empirical model, which explicitly expresses the errors due to the conventional use of Matthiessen´s rule as a function of both the lowest subband population and the relative strength of individual mobility components. The model holds under practical conditions (with temperatures up to 400 K) and in a broad range of substrate doping concentrations (10¹⁴ to 10¹⁸ cm^-3). To make the error-free proposal more general, we elaborate on several issues, including strain, impurity Coulomb scattering, and remote scattering. The thin-film case can be treated accordingly.