Electrical properties of rapid thermal annealed carbon-doped InGaAs grown by atmospheric pressure metalorganic chemical vapor deposition

Abstract

We present the changes in the carrier concentration and the mobility of heavily carbon-doped InGaAs epilayers caused by rapid thermal annealing (RTA). In the region of low InAs mole fraction, the hole concentration shows a peak at a RTA temperature of 650 degrees C. Beyond this temperature, the hole concentration decreases. However, its value is still higher than that of as-grown InGaAs epilayers. The maximum value of the hole concentration is measured to be 3.3x10(20) cm(-3) at an InAs mole fraction of 0.09 after RTA. The type conversion from p-type to n-type is observed at an InAs mole fraction of 0.44 and 0.48 for the rapid thermal annealed and the as-grown carbon-doped InGaAs epilayers. For the case of In0.52Ga0.48As epilayers, the carrier concentration increases gradually with increment of annealing temperature. This can be explained by the fact that carbon atoms broken by thermal energy occupy the substitutional In sites in the In0.52Ga0.48As epilayer.