Deposition of SnSxOy films by electrochemical deposition using three-step pulse and their characterization

We deposited tin sulfide (-oxide) films by the electrochemical deposition (ECD) from an aqueous solution containing SnSO4 and Na2S2O3. This technique is simple and cost-effective, and the films can be deposited on a large area with reasonable quality. We used a new potential pulse form called the three-step pulse, consisting of reduction (deposition), oxidation (dissolution), and intermediate (diffusion) steps. We optimized the diffusion step potential considering the surface morphology, and found that under optimized pulse conditions, surface morphology and photosensitivity were improved compared with those in the two-step pulse case. Considering the current profile during deposition, the effects of introducing the diffusion step on both surface morphology and film composition were discussed in details. (author)