The Optical and Electrical Characteristics of ZnS:In Thin Films Prepared by Chemical Bath Deposition Method

Zinc sulfide (ZnS) buffer layer is one of the most promising potential candidates for solar applications due to its no toxicity, wider energy bandgap compared with cadmium sulfide (CdS) buffer layers. The ZnS thin films doped with 0–4 at% In have been grown by a Chemical Bath Deposition (CBD) method. The X-ray diffraction analysis indicates that all the films show an obvious peak corresponding to (111) plane of cubic form ZnS. All the ZnS:In films have a high transmittance of about 85% in the visible region with a high energy bandgap of about 3.60 eV. The electrical resistivity of the In-doped samples is decreased from 10 6 Ω·cm (undoped sample) to 10 4 Ω·cm after doping with 0.5 at% In. The detailed analysis about the change of bandgap, resistivity and other results with the In dopant concentration would be presented and discussed.