Designing Precursors for the Deposition of Tin Sulphide Thin Films

Abstract

This paper reviews the work carried out by the authors over the last three years on the deposition of tin sulphide films. Particular emphasis is placed on the design and limitations of single-source precursors for these films. Simple homoleptic thiolates Sn(SR) 4 only generate tin sulphides in combination with H 2 S, otherwise Sn 3 0 4 is produced by in situ formation of Sn(0) and subsequent oxidation. This problem is overcome by the use of chelating dithiolates. The decomposition of mixed ligand (RS) 2 Sn(S2CNEt2)2 are also described, as are the synthesis and structures of mixed metal thiolates (Ph 3 PP)AuSSnCy 3 and PhHgSSnCy 3 , potential precursors for ternary tin-containing sulphides.

Deposition of SnS Thin Films from Sn(II) Thioamidate Precursors

“…SnS thin films have been deposited by ALD, , spray pyrolysis, − sputtering, − chemical bath deposition, − vacuum evaporation, − and CVD. ,− In this latter regard, an initial report by Price et al described the use of atmospheric pressure (AP) CVD to deposit a variety of tin sulfide stoichiometries from SnCl 4 and H 2 S in the temperature range 300–545 °C, , albeit SnS was only obtained at 545 °C. Similarly, (fluoroalkylthiolato)­tin­(IV) and organotin­(IV) dithiocarbamates have been reported to provided SnS under APCVD conditions with the addition of H 2 S. ,, The tin thiolate precursor, (PhS) 4 Sn, has also allowed SnS deposition in the temperature range 350–500 °C, both with and without the presence of H 2 S by aerosol-assisted (AA) CVD. , All the deposited films were amorphous, although Raman spectroscopy and EDX analysis confirmed the presence of tin sulfide.…”