Deep level defects in AlxGa1-xN/GaN heterointerfaces grown by molecular beam epitaxy

Abstract

Capacitance-voltage (C-V) and Deep-level transient spectroscopy (DLTS) measurements on AlxGa1-xN/GaN heterostructures were performed to investigate the existence of the carriers and the behavior of the deep levels in the AlxGa1-xN/GaN heterointerface. The C-V depth profile showed that the carrier concentration existed at the Al xGa1-xN/GaN heterointerface was 4 × 1012 cm2. The DLTS results showed two deep levels. The capture cross-section of the deep level related to the two-dimensional electron gas decreased with increasing depth, resulting from the existence of the different deep levels in each region.