Epitaxy control of InN-based III-nitrides towards development of novel nanostructure photonic devices

Abstract

About five years have already passed since the finding of the “new” energy bandgap of InN around 0.7 eV. Several questions regarding the real validity and/or usefulness of InN for device applications have then been often raised. Recently, significant progress has been made in the epitaxy control of InN-based III-nitrides under the In-polarity growth regime by molecular beam epitaxy (MBE) as well as in the fabrication of their novel nanostructures. In this paper, we review the following remarkable trials and achievements in both the nanoprocesses and nanodevice structures of InN-based III-nitrides towards the development of high-functionality photonic devices: 1) the realization of atomically flat surface/interface under the In-polarity growth regime, 2) reduction in the concentration of residual donors and a trial for p-type doping, and 3) the proposal and realization of high-quality InN/GaN multiple quantum wells (MQWs) consisting of one monolayer InN wells inserted in GaN matrix.