Electrical characterisation of Sn doped InAs grown by MOVPE

Abstract

The feasibility of tetraethyl tin (TESn) as an n‐type dopant for InAs is investigated. The electrical properties of Sn doped InAs films grown on semi‐insulating GaAs substrates by MOVPE are extensively studied as a function of substrate temperature, V/III ratio, substrate orientation and TESn flow rate. Results from this study show that Sn concentrations can be controlled over 2 orders of magnitude. The Sn doped InAs layers exhibit carrier concentrations between 2.7 x 1017 and 4.7 x 1019 cm–3 with 77 K mobilities ranging from 12 000 to 1300 cm2/Vs. Furthermore, the influence of the variation of these parameters on the structural properties of InAs are also reported. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)