Low electric field hole impact ionization coefficients in GaInAs and GaInAsP

The electric field dependence of the hole impact ionization coefficients in Ga/sub 0.47/In/sub 0.53/As and Ga/sub 0.28/In/sub 0.72/As/sub 0.61/P/sub 0.39/ was obtained from the electrical characteristics of p-n-p heterojunction bipolar transistors. The anomalous low field behavior of the electron impact ionization coefficients in these materials was not observed for the case of holes. Within the accuracy of our measurements me observed no change in the hole ionization rates in the temperature range of 20 to 120/spl deg/C.