Single-Crystal Growth of Cl-Doped n-Type SnS Using SnCl2 Self-Flux

SnS is a promising photovoltaic semiconductor owing to its suitable band gap energy and high optical absorption coefficient for highly efficient thin film solar cells. The most significant carnage is demonstration of n-type SnS. In this study, Cl-doped ntype single crystals were grown using SnCl2 self-flux method. The obtained crystal was lamellar, with length and width of a few millimeters and thickness ranging between 28 and 39 mu m. X-ray diffraction measurements revealed the single crystals had an orthorhombic unit cell. Since the ionic radii of S2- and Cl- are similar, Cl doping did not result in substantial change in lattice parameter. All the elements were homogeneously distributed on a cleaved surface; the Sn/(S + Cl) ratio was 1.00. The crystal was an n-type degenerate semiconductor with a carrier concen- tration of similar to 3 x 10(17) cm(-3). Hall mobility at 300 K was 252 cm(2 )V(-1) s(-1) and reached 363 cm(2) V-1 s(-1) at 142 K.