Electron beam evaporated carbon doping of InGaAs layers grown by gas source molecular beam epitaxy

Abstract

We have studied carbon doping of GaInAs grown by gas-source molecular beam epitaxy. Graphite was used as a source material for carbon evaporation. GaInAs was studied due to its importance as a base layer in InP-based heterojunction bipolar transistors. We show that useful p-type acceptor concentrations can be achieved by evaporation from graphite source for GaInAs grown by gas-source molecular beam epitaxy. Secondary ion mass spectroscopy and Van der Pauw Hall measurements were used to characterise the carbon and net acceptor concentrations of the GaInAs layers. The effect of rapid thermal annealing on acceptor concentrations and Hall mobilities was also studied.