Temperature dependence of carrier mobility in Si wafers measured by infrared photocarrier radiometry

Abstract

A recently introduced infrared photocarrier radiometry technique has been used to determine the temperature dependence of carrier mobility in Si wafers. In addition, its potential to determine simultaneously the carrier lifetime, diffusion coefficient, and surface recombination velocity is reported. This noncontact, nonintrusive, and all-optical technique relies on the detection of infrared radiation from harmonically excited free carriers (pure electronic diffusion-wave detection). Using a multiparameter fitting to a complete theory, the results showed that the lifetime increases with temperature, the diffusion coefficient decreases ${\mathrm{[D(T)\sim T}}^{\text{−1.5}}\mathrm{],}$ and the temperature dependence of carrier mobility is ${\text{μ(T)=(1.06±0.07)×10}}^9{\mathrm{\times T}}^{\text{−2.49±0.01}}\hspace{0.5em}{\mathrm{cm}}^2/\mathrm{V s}.$