Influence of Bath Temperature on CBD-CdS Thin Films

CdS thin films were grown on conducting glass substrates at different bath temperatures in order to investigate their influence on opto-electrical properties of the chemical bath deposited (CBD) CdS thin films. The CBD-CdS process was carried out with 0.001 M CdSO4, 0.002 M CS(NH2)2 and NH3 solution at different bath temperatures from 40 to 80 0C for one hour. Fabricated films were characterized using UV-Vis spectrometry, SEM, PEC cell and Profilometer.The optical transmittances of the films decreased with increasing bath temperature due to the increase of the film thickness. CdS cluster size of the thin films grown in the bath at a temperature of 60 0C was considerably larger compared to the films fabricated at other bath temperatures. The variation of optical band gap (Eg) was found to be in good agreement with cluster size variation while electrical characterizations reveal considerably high Voc and Isc values for the films fabricated at a bath temperature of 80 0C.