Highly textured ZnO thin films: a novel economical preparation and approachment for optical devices, UV lasers and green LEDs

Abstract

Fabrication of high quality ZnO thin films and analysis on its physical, chemical properties have applications in opto-electronic devices, UV laser, green LEDs, microelectronics and micro-machining technologies. In the present investigation, highly textured zinc oxide (ZnO) thin films with a preferred (1 0 1) orientation were prepared by chemical bath deposition using a sodium zincate bath on glass substrates. The films were characterized by Philips-Xpert MPD-XRD, Hitachi-SEM, EDAX, Optical, FTIR and PL in order to justify the suitability for commercial device quality. The effects of number of dippings on thin film growth and allied properties were investigated. Highly ASTM standard polycrystalline textured thin films contain nano-grains were observed by XRD. The material (ZnO) was confirmed by EDAX and FTIR. SEM reveals the presence of uniform adherent thin film. Increasing in grain size (nm) and decreasing in PL intensity were observed, while increasing the number of dippings. The optimized ZnO thin films have average transmission 85% in the visible range. Optical and PL studies demonstrated the suitability of the prepared films for optical devices, UV lasers and green LEDs.