Investigation on structural, optical and electrical behaviours of Sn doped copper oxide thin films and fabrication of diode

Tin doped copper oxide (Sn:CuO) thin films are deposited on glass substrate with different Sn ( 2, 4 and 6 wt%) concentration using spray pyrolysis technique at an ambient substrate temperature of 600 °C. Monoclinic structure of the synthesized materials are confirmed by the XRD analysis, the average crystallite size of the coated materials are calculated using Scherrer’s formula and found to decrease with increase in Sn concentration. The average grain size of the Sn doped CuO thin films are measured from the SEM images using image J software. The EDAX graph confirms the presence of Sn in the CuO lattice. Absorption spectra of synthesized films show the increase in the absorption of incident radiation in the visible region with increase in doping of Sn ions. The refractive indices of the CuO thin films increase with the increasing of Sn concentration is observed with help of Swanepoel’s envelope relation. The band gap of the fabricated films are calculated using Tauc’s relation, it is found to decrease with the increase in Sn concentration. I–V characteristics of the samples are studied using Keithley electrometer 6517B with two probe setup from which DC conductivity had been calculated. p -SnCuO/ n -Si (2, 4 and 6% of Sn doped with CuO) diodes are fabricated using jetnebulizer spray pyrolysis technique. The diode parameters are calculated with the help of JV method and it was predicted that the Sn doped CuO diodes posses the better rectification characteristic compared to pure p -CuO/ n -Si diode.