STRUCTURAL, OPTICAL AND ELECTRICAL PROPERTIES OF Al-DOPED ZnO TRANSPARENT CONDUCTING OXIDE FOR SOLAR CELL APPLICATIONS

摘要

Al-doped zinc oxide (AZO) thin films are deposited onto glass substrates using radio-frequency reactive magnetron sputtering and the improvements in their physical properties by post-synthesis thermal treatment are reported. X-ray diffraction spectra show that the structure of films can be controlled by adjusting the annealing temperatures, with the best crystallinity obtained at 400℃ under a nitrogen atmosphere. These films exhibit improved quality and better optical transmittance as indicated by the UV-Vis spectra. Furthermore, the sheet resistivity is found to decrease from 1.87 × 10~(-3) to 5.63 × 10~(-4)Ω• cm and the carrier mobility increases from 6.47 to 13.43 cm~2 • V~(-1) • s~(-1) at the optimal annealing temperature. Our results demonstrate a simple yet effective way in controlling the structural, optical and electrical properties of AZO thin films, which is important for solar cell applications.