MICROWAVE PHOTOCONDUCTIVE MIXING IN N-TYPE AND P-TYPE COMPENSATED SILICON

Low-temperature photoconductive mixing measurements have been performed on n- and p-type compensated Si at a microwave beat frequency of 253 MHz. The dependence of the transport parameters (electron-hole recombination lifetime and drift velocity) on temperature and electric field obtained from this experimental technique, are discussed. At high temperatures (T greater-than-or-equal-to 35 K for n-type and T greater-than-or-equal-to 60 K for p-type), the drift velocity is determined by neutral impurity and ionized impurity, and charge carrier-phonon scattering. In the carrier freeze-out regime (T less-than-or-equal-to 35 K for n-type, T less-than-or-equal-to 60 K for p-type) hopping charge transport is the dominant mechanism determining the drift velocity.