Authors: Shruti Verma Sushil Kumar Pandey Mukul Gupta Shaibal Mukherjee
Publish Date: 2014/06/26
Volume: 49, Issue: 20, Pages: 6917-6929
Abstract
CdZnO thin films with a nominal thickness of ~200 nm were grown on cplane sapphire substrates by dual ionbeam sputtering deposition technique The effect of substrate temperature 300–600 °C and gas ambience on structural morphological compositional and optoelectronic properties was studied Xray diffraction patterns confirmed that all the films were polycrystalline in nature and were preferentially oriented along the caxis It was revealed that the films grown at Ar/O2 ratio of 41 were structurally more ordered and the film quality was found to be the best at 500 °C The compositional studies specify that approximately 118 at of cadmium were present in the film deposited at 300 °C in Ar–O2 mixture Investigations on optical properties by photoluminescence and absorption studies indicate band gap shrinkage with the increase in argon partial pressure and substrate temperature It was found that photosensitivity of the deposited films was highly dependent on growth conditions The photosensitivity was found to be 5000fold higher for CdZnO film grown at 600 °C in Ar–O2 ambience compared to the best reported result and this was promising to realize highperformance optoelectronic devices on such CdZnO filmsThis work was partially supported by Department of Science and Technology DST Fast Track Scheme for Young Scientist No SR/FTP/ETA101/2010 DST Science and Engineering Research Board SERB Project No SR/S3/EECE/0142/2011 and Council of Scientific and Industrial Research CSIR Project No 220608/12/EMRII We are also grateful to the AFM Facility equipped at Sophisticated Instrument Centre at IIT Indore and T Shripathi and U P Deshpande UGCDAE Indore for XPS Facility
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