Chemical Vapor Deposition of MoS₂and TiS₂Films From the Metal−Organic Precursors Mo(S-t-Bu)₄and Ti(S-t-Bu)₄

The deposition of MoS 2 and TiS 2 thin films from the metal-organic precursors Mo(S- t -Bu) 4 and Ti(S- t -Bu) 4 has been investigated. Stoichiometric films with low levels of oxygen and carbon contaminants can be grown at temperatures between 110 and 350 °C and low pressure. The films are amorphous when grown at these low temperatures and have granular morphologies in which the grains are 30−90 nm in diameter, the larger grain sizes being observed at higher deposition temperatures. For the MoS 2 deposits, the electrical conductivity was ∼1 Ω - 1 cm - 1 . For both precursors, the organic byproducts generated during deposition consist principally of isobutylene and tert -butylthiol; smaller amounts of hydrogen sulfide, isobutane, di- tert -butyl sulfide, and di- tert -butyl disulfide are also generated. A β-hydrogen abstraction/proton-transfer mechanism accounts for the distributions of the organic byproducts seen during the deposition of MoS 2 and TiS 2 films. Our results differ in some respects from those of a previous study of the deposition of thin films from the titanium thiolate precursor.