Abstract
Abstract We investigate the effect of rapid thermal annealing on Carbon-doped InGaAs/InP heterojunction bipolar transistors（HBT's）.We predicted that, after 700℃ annealing, the p-type dopant can be increased by an order of magnitude, but the InGaAs base doping concentration shows that only about 2-3 fold dopant activation after RTA process. This could be attributed to hydrogen passivation during the growth. However, because of base dopant is activated, not additionally introduced, and less base current are spent on the space-charge recombination,higher gain can be anticipated for RTA device. Finally, we will also present the current gain which is over 100 by reducing the spacer thickness.