Synthesis and characterization of Ga-doped ZnO nanodisk and the formation of nanodisk/nanorod hybrid morphologies on AlN/Si substrate by polymer assisted one-pot hydrothermal process have been studied. The low concentration of Ga-ZnO sol (0.2 M) and optimized concentration (0.5 M) of Zinc sol is used to vary the morphology and physico-chemical properties. Varying amounts of Ga (1%-3%) doped ZnO nanodisks have also been synthesized and characterized. The morphology and structural properties were determined by field emission scanning electron microscopy (FESEM) and X-ray diffraction techniques. Ga-ZnO nanodisk shows major intense X-ray diffraction peak at ZnO (101). X-ray photoelectron spectroscopy (XPS) confirms the effect of gallium doping and variation in their surface property after Ga doping in ZnO. FESEM images clearly confirm the pure nanodisk formation for Ga-ZnO (0.5) at optimized ZnO concentration and hybrid nanodisk/nanorod formation obtained for Ga-ZnO (0.2) at lower ZnO concentration. The pure Ga-ZnO (0.5) nanodisk on AlN/Si thin film substrate showed effective response and fast recovery time towards UV light sensing in dark condition compared to low concentration route prepared Ga-ZnO (0.2)/AlN/Si sample. (C) 2013 Elsevier B.V. All rights reserved.