ANOMALOUS SILICON AND TIN DOPING BEHAVIOR IN INDIUM-PHOSPHIDE GROWN BY CHEMICAL BEAM EPITAXY

Anomalous behaviour of the most commonly used n-type dopants, Si and Sn, has been observed in the growth of InP by chemical beam epitaxy. For Si, the doping level is found to decrease with time. It is postulated that this is due to the formation of carbon and silicon carbide deposits in the dopant cell. The behaviour of Sn is more complex. For Sn cell temperatures in the range 600-750°C incorporation is proportional to the Sn vapour pressure. However, at low temperatures, 175-350°C, anomalously large incorporations of Sn are observed. This behaviour is attributed to the formation of a volatile metalorganic species within the Sn cell. © 1990.