Investigation on structural, optical and electrical properties of Cp2Mg flow varied p-GaN grown by MOCVD

Abstract

In this work the effect of different concentration of Magnesium doped GaN (p-GaN) were systematically studied. The p-GaN epilayers were grown on c-plane sapphire substrate by horizontal flow Metal Organic Chemical Vapor Deposition (MOCVD) with various flow rates of 100 sccm to 300 sccm using bis-(cyclopentadienyl) - magnesium (Cp2Mg) precursor. The samples were subjected to structural, optical, morphological and electrical studies using High Resolution X-ray diffraction (HRXRD), room temperature photoluminescence (PL), Atomic Force Microscopy (AFM) and Hall measurement respectively. Results indicated that the Mg doped GaN of 200 sccm Cp2Mg has the root mean square (rms) roughness of about 0.3 nm for a scan area of 5×5 µm2 which has good two dimensional growth. Moreover, Hall measurements results shows that (200 sccm Cp2Mg) Mg-doped GaN possess the highest hole concentration of 5.4×1017cm−3 and resistivity of 1.7 Ωcm at room temperature.