Li doped ZnO thin film: effect of substrate temperature on structure, optical and electrical properties

RF magnetron sputtering technique was employed to deposit Li-doped ZnO thin films onto quartz substrate at different substrate temperatures ranging from room temperature (RT) to 500 $$^{\circ }\hbox {C}$$∘C. X-ray diffraction analysis revealed that the deposited films had a hexagonal-wurtzite crystal structure with preferred orientation along the c-axis. Increasing the substrate temperature improved the crystallinity and caused a significant increase in the crystallite size (182 nm) for the film deposited at 500 $$^{\circ }\hbox {C}$$∘C. The energy band gap of the films deposited at RT, 350, 400, 450 and 500 $$^{\circ }\hbox {C}$$∘C were found to be 3.292, 3.282, 3.281, 3.28 and 3.269 eV, respectively. All films exhibited a broad UV-violet emission band centered on 407 nm and attributed to the radiative recombination processes near the band edge. A Hall mobility of $$\sim $$∼33.3 $$\hbox {cm}^{2}$$cm2/V s, concentration ($$n$$n) of $$\sim $$∼7.6 $$\times 10^{18}\,\hbox {cm}^{-3}$$×1018cm-3 and resistivity of $$\sim $$∼39.7 $$\Omega $$Ω-cm were obtained for the film deposited at 500 $$^{\circ }\hbox {C}$$∘C. The results show that the substrate temperature plays a crucial role in the structural, morphological, optical and electrical properties.