A Comparative Study: Sequential and Single-Step-Electrodeposited CZTS Thin Films

Abstract

CZTS (Cu2ZnSnS4) is a relatively new and promising semiconductor material suitable for photovoltaic applications due to its favorable optoelectronic properties. Of the many techniques available for growing these films, a comparative study on sequential and single-step electrodeposition methods to grow CZTS films is carried out in this investigation to explore the possibility of improving the quality of the films using the inexpensive electrodeposition technique. Mainly in both methods, potentiostatic electrodeposition technique is adopted for growing CZTS thin films. In both methods, growth conditions of the CZTS films are optimized after measuring the photoresponses in a photoelectrochemical (PEC) cell of the films that resulted at the end of each deposition step. The observed structural and optoelectronic properties of the films reveal that, in general, structurally good and photoactive CZTS films can be prepared using both methods. Moreover, photoresponse and Mott–Schottky measurements on CZTS films in a PEC reveal that CZTS films prepared using the single-step electrodeposition have better photoactive properties and improved doping densities. This important finding shows that when developing CZTS-based solar cells using the inexpensive electrodeposition technique, single-step electrodeposition is more advantageous.