Pulse plated SnSe films

Abstract

In this work, the pulse electrodeposition technique has been employed for the first time to deposit SnSe films. SnSe films were deposited by the pulse electrodeposition technique at room temperature from a bath containing Analar grade 50 mM tin chloride (SnCI4) and 5 mM SeO2. The deposition potential was maintained as - 0.9V (SCE). Tin oxide coated glass substrates (5.0 ohms/ sq) was used as the substrate. The duty cycle was varied in the range of 6 - 50%. The XRD profile of SnSe thin films deposited at different duty cycles indicate the peaks corresponding to SnSe. Atomic force microscopy studies indicated that the surface roughness increased from 0.5 nm to 1.5 nm. The transmission spectra exhibited interference fringes. The value of refractive index at 780 nm was 2.1, this value decreased to 1.95 with decrease of duty cycle. The room temperature resistivity increased from 0.1 ohm cm to 10 ohm cm with decrease of duty cycle. Photoelectrochemical cell studies were made using the films deposited at different duty cycles. For duty cycles greater than 15% photo output was observed. For a film deposited at 50% duty cycle, an open circuit voltage of 0.55 V and a short circuit current density of 5.0 mA cm-2 at 60 mW cm-2 illumination. Capacitance voltage measurements indicated Vfb = 0.67 V (SCE) and p type, carrier density = 6.98 × 1016/ cm3.