We prepared SnSx thin films on both soda-lime glass (SLG) and molybdenum(Mo)/SLG substrates by a two-step process using a Sn precursor followed by sulfur reaction in rapid thermal annealing (RTA) at different sulfurization temperatures (Ts = 200℃, 230℃, 250℃, and 300℃) and annealing times (ts = 10 min and 30 min). The single SnS phase was dominant for 200℃≤Ts<250℃, while an additional phase of SnS2 was appeared at Ts≥250℃ alongside SnS. The SnS grains in all the samples showed strong growth along the preferred [040] direction. The band-gap energy (Eg) of the films was estimated to be 1.24 eV.
Transparent UV photodetector was achieved by using wide bandgap metal oxide materials. In order to realize transparent heterojunction UV photodetector, n-type ZnO and p-type NiO metal oxide materials were employed. High light-absorbing SnS layer was inserted into the n-ZnO and p-NiO layers. High-performing UV photodetector was realized by ZnO/SnS/NiO/ITO structures to provide extremely fast response times (Fall time: 7 μ s and rise time: 13 μs) and high rectifying ratio. The use of functional SnS-embedded photodetector would provide a route for high functional photoelectric devices.
We fabricated a tin sulfide (SnS) layer with Sn/Mo/glass layers followed by a RTP (rapid thermal processing), and studied the film growth and structural characteristics as a function of annealing temperature and time. The elemental sulfur (S) was cracked thermally and applied to form SnS polycrystalline film out of the Sn percursor at pre-determined pressures in the RTP tube. The sulfurization was done at the temperature from 200℃ to 500℃ for a time period of 10 to 40 min. At ≤ 300℃, 20 min., p-type SnS thin films was grown and showed the best composition of at.% of [S]/[Sn] . 1 and [111] preferred orientation as investigated from using XRD (X-ray diffraction) analysis and EDS (energy dispersive spectroscopy) and SEM (scanning electron microscopy), and optical absorption by a UV-VIS spectrometer. In this paper, we report the details of growth characteristics of single phase SnS thin film as a function of annealing temperature and time associated with the pressure and ambient gas in the RTP tube.