Point-defect management in homoepitaxially grown Si-doped GaN by MOCVD for vertical power devices

Abstract

We demonstrate controlled Si doping in the low doping range of 5 × 1015–2.5 × 1016 cm−3 with mobility >1000 cm2 V−1 s−1 in GaN films grown by metalorganic chemical vapor deposition. The carbon-related compensation and mobility collapse were prevented by controlling the electrochemical potential near the growth surface via chemical potential control (CPC) and defect quasi-Fermi level (dQFL) point-defect management techniques. While the CPC was targeted to reduce the net CN concentration, the dQFL control was used to reduce the fraction of C atoms with the compensating configuration, i.e. The low compensating acceptor concentration was confirmed via temperature-dependent Hall effect analysis and capacitance–voltage measurements.