Indium-surfactant-assisted epitaxial growth of semi-polar (11(2)over-bar2) plane Al0.42Ga0.58N films

The semi-polar (11 (2) over bar2) plane Al0.42Ga0.58N films were successfully grown on (10 (1) over bar0) oriented m-plane sapphire substrates for the first time with an indium (In)surfactant- assisted metal-organic chemical vapor deposition (MOCVD) technology. The crystal orientation, surface morphology, and electrical properties of the grown semipolar (11 (2) over bar2) plane AlGaN epi-layers were characterized with high-resolution X-ray diffraction (HR-XRD), atomic force microscopy (AFM), and Hall effect measurements, respectively. The XRD scanning results showed that crystalline quality for the semi-polar (11 (2) over bar2) plane AlGaN epilayer was improved with In-surfactant. The AFM results demonstrated that the root mean square value of the semipolar AlGaN epi-layer samples decreased with increasing the TMIn mole flow rate. Furthermore, the native electron concentration of the unintentionally doped semi-polar (11 (2) over bar2) plane AlGaN epi-layers was decreased from 2.66 x 10(17) to 2.97 x 10(16) cm(-3) due to the significant decrease in nitrogen vacancies (VN) with indium-surfactant-assisted growth process.