Tin() chalcogenoether complexes as single source precursors for the chemical vapour deposition of SnE and SnE (E = S, Se) thin films

• Published in: Dalton transactions : an international journal of inorganic chemistry 2018-02, Vol.47 (8), p.2628-2637
• Main Authors: Gurnani, Chitra, Hawken, Samantha L, Hector, Andrew L, Huang, Ruomeng, Jura, Marek, Levason, William, Perkins, James, Reid, Gillian, Stenning, Gavin B. G
• Format: Article
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/c7dt03848h

The molecular Sn( iv ) complexes, [SnCl 4 { n BuS(CH 2 ) 3 S n Bu}] ( 2 ), [SnCl 4 ( n Bu 2 S) 2 ] ( 3 ) and [SnCl 4 ( n Bu 2 Se) 2 ] ( 4 ) have been prepared in good yield from reaction of SnCl 4 with the appropriate chalcogenoether ligand in anhydrous hexane and, together with the known [SnCl 4 { n BuSe(CH 2 ) 3 Se n Bu}] ( 1 ), employed as single source precursors for the low pressure chemical vapour deposition of the corresponding tin dichalcogenide thin films. At elevated temperatures the bidentate ligand precursors, ( 1 ) and ( 2 ), also form the tin monochalcogenides, SnSe and SnS, respectively. In contrast, ( 3 ) gave a mixture of phases, SnS 2 , Sn 2 S 3 and SnS and ( 4 ) gave SnSe 2 only. The morphologies, elemental compositions and crystal structures of the resulting films have been determined by scanning electron microscopy, energy dispersive X-ray spectroscopy, grazing incidence X-ray diffraction and Raman spectroscopy. Van der Pauw measurements on the SnS 2 , SnS and SnSe 2 films confirm their resistivities to be 2.9(9), 266(3) and 4.4(3) Ω cm, respectively. Distorted octahedral complexes of Sn( iv ) with thio- and seleno-ether ligands have been used as single source precursors in low pressure CVD experiments under various conditions to deposit tin mono and dichalcogenide thin films.