Investigations on SnS

Abstract

The p, T, x diagram of the Sn-S system was determined especially in the region of the compound SnS. The pressure of S2 in equilibrium with SnS and a liquid phase was found to extend over several decades up to 25-mm Hg at the ``Sn-rich'' side, whereas at the ``S-rich'' side the S2 pressures in equilibrium with solid SnS and a liquid phase lie between 25-mm Hg and 100-mm Hg. It was shown that the existence region of solid SnS very probably lies entirely at the excess sulfur side. The hole mobility in a plane perpendicular to the c axis, ≈90 cm2/v sec at room temperature, was proportional to T−2,2 for higher temperatures. The mobility in the direction of the c axis was about five times smaller. Reversible annealing effects were found for temperatures above 200°C which could be explained by assuming association of neutral Sn vacancies. Absorption measurements showed that the edge absorption is due to indirect transitions. The bandgap was 1.08 ev at 300°K and 1.115 ev at 77°K. Interband transitions in the valence band were also found. The effective charge of the atoms (e*=0.7e0) and the effective masses of the holes in the three principal crystal directions (ma*=mb*=0.20m0; mc*≈m0) were determined from reflection measurements in the infrared. From these values and the value for the density of states mass obtained by means of the Seebeck effect (md*≥0.95m0), the number of equivalent maxima of the valence band was found to be at least four.

Antimony-Doped Tin(II) Sulfide Thin Films

“…Albers et al reported the use of Sb as a dopant that lowers the hole concentration of SnS to be less than 10 14 cm -3 . 13 Nonetheless, the specific Sb concentration and detailed studies of its effect on the electrical properties of SnS were not reported. By increasing the Sb concentration further, it might be possible to convert SnS to an n-type semiconductor.…”

“…12 This approach requires SnS to have a low carrier concentration on the order of 10 13 cm -3 , which is lower than typical undoped SnS values of 10 15 -10 18 cm -3 . 3,4,6,13 Therefore, the ability to control carrier concentration and conduction type of SnS could improve SnS-based thin film solar cells and, in general, could broaden the utility of SnS as an optoelectronic semiconductor outside the field of photovoltaics.…”

“…SnS can be doped by Ag 13,14 and Cu 15 to increase its hole concentration to around 10 19 cm -3 . Dussan et al attempted to use Bi to substitute Sn in SnS to provide n-type conduction, but the material remains p-type below 50% Bi concentration.…”

Optimization of parameters of chemical spray pyrolysis technique to get n and p-type layers of SnS

“…Tin (II) sulfide (SnS) is one such material, which has high potential in device fabrication due to its non-toxicity and easy availability of the constituent materials. It is a IV-VI layered compound semiconductor with distorted NaCl type orthorhombic crystal structure [3]. Due to its interesting structural, optical and electrical properties, SnS has become an important material for optoelectronics and photovoltaics [4][5][6][7] with many promising technological applications [8,9].…”

“…Electronic structure and structural calculations of SnS were deduced from photoelectron spectra by Ettema et al [13]. Optoelectronic properties suitable for the device fabrication were also reported by several groups [3][4][5][6][7].…”