Abstract
Tin sulfide (SnS) thin films were deposited at room temperature (RT) by thermal evaporation method and subsequently annealed at 150–350 °C in N
2
atmosphere. The influence of annealing temperature on composition, structural, morphological and optical properties of the thin films has been investigated. X-ray diffraction (XRD) analysis and Raman studies confirmed the formation of single phase SnS films at RT and annealed up to 300 °C. The crystallite size increased from 24 nm for as-deposited film to 37 nm for the 300 °C annealed film and further reduced to 18 nm for the 350 °C annealed film. The film annealed at 200 °C was found to have better morphological features with (111) preferred oriented crystallites. The absorption coefficient, optical band gap (
E
g
) of the deposited films were estimated from the optical transmittance measurements. Photodetectors are fabricated by depositing Ag contacts on SnS thin films using a metal mask and photo response was tested under dark and illumination conditions using 532 nm laser of varying power intensities. The photodetectors performance is evaluated using responsivity (
R
), external quantum efficiency (EQE), and specific detectivity (
D
*). The specific detectivity of 6.8 × 10
10
Jones obtained in the present study is nearly two orders of magnitude greater than that reported earlier.