Defect reduction of SiNx embedded m-plane GaN grown by hydride vapor phase epitaxy

•Optical and crystal qualities of m-GaN were improved by SiNx interlayer.•XRC FWHMs and anisotropy of m-GaN were decreased by SiNx interlayer.•Detects were bent and annihilated via a SiNx interlayer into m-GaN epilayer.

Nonpolar (1 0 −1 0) m-plane GaN has been grown on m-plane sapphire substrates by hydride vapor phase epitaxy (HVPE). We studied the defect reduction of m-GaN with embedded SiNx interlayers deposited by ex-situ metal organic chemical vapor deposition (MOCVD). The full-width at half-maximum values of the X-ray rocking curves for m-GaN with embedded SiNx along [1 1 −2 0]GaN and [0 0 0 1]GaN were reduced to 528 and 1427 arcs, respectively, as compared with the respective values of 947 and 3170 arcs, of m-GaN without SiNx. Cross-section transmission electron microscopy revealed that the basal stacking fault density was decreased by approximately one order to 5×104 cm−1 due to the defect blocking of the embedded SiNx. As a result, the near band edge emission intensities of the room-temperature and low-temperature photoluminescence showed approximately two-fold and four-fold improvement, respectively.