Chemical vapor deposition of MoS2 and TiS2 films from the metal-organic precursors Mo(S-t-Bu)(4) and Ti(S-t-Bu)(4)

The deposition of MoS2 and TiS2 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 degrees 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 MoS2 deposits, the electrical conductivity was similar to 1 Ohm(-l)cm(-l). 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 P-hydrogen abstraction/proton-transfer mechanism accounts for the distributions of the organic byproducts seen during the deposition of MoS2 and TiS2 films. Our results differ in some respects from those of a previous study of the deposition of thin films from the titanium thiolate precursor.