Measurement of the electron drift velocity in InSb up to fields of 800 V/cm in the presence of impact ionization

摘要

AbstractThe results of experimental investigation of the electron drift velocity (DV) as a function or electric field are presented for n‐InSb as determined from the measurements of the average microf wave (MW) conductivity at 77 K. In the samples studied an exponential growth of carrieconcentration in time due to impact ionization by the MW field is suppressed by fast recombination, the rate of which increased with the MW field. To find the nonequilibrium carrier concentration the MW field is switched off for a time interval short compared to the lifetime of excess carriers. The maximum DV as determined by this technique is 5.5 × 107cm/s and the threshold field for the appearance of negative differential mobility (NDM) is in the range 500 to 580 V/cm. From the analysis of the experimental data it is concluded that up to fields of 800 V/cm the ionization frequency is much smaller than the phonon scattering frequen