Bis(tert-butyl)gallium dimethyldithiocarbamate Ga(tBu)2 (S2CNMe2)
Bis(tert-butyl)gallium dimethyldithiocarbamate (tBu)2Ga(S2CNMe2) is air stable low melting point solid allowing its use as liquid precursors for MOCVD. It was synthesized by the reaction of [(tBu)2Ga(μ-Cl)]2 with 1 molar equivalent of Na(S2CNR2). Pure (tBu)2Ga(S2CNMe2) was obtained by sublimation, separating it from bis-substituted (tBu)Ga(S2CNMe2)2 formed as minor product. The molecular structure of (tBu)2Ga(S2CNMe2) was determined by X-ray crystallography; the vaporization enthalpy (ΔHv) was obtained from thermogravimetry.
Bis(tert-butyl)gallium dimethyldithiocarbamate (tBu)2Ga(S2CNMe2) has been applied as single-source precursor for the growth of gallium sulfide (GaS) thin films at 375−425 °C by atmospheric pressure MOCVD. Film composition was Ga:S =1:1 with a low degree of impurities (C <3%; O <1%), as was determined by wavelength dispersive spectroscopy (WDS) microprobe analysis. Gallium-rich films were grown using (tBu)2Ga(S2CNMe2) under reduced pressure. Abundance of N on the surface of GaS films was revealed by XPS studies and SIMS measurements. GaS films had a new distorted hexagonal wurtzite phase (a = 4.590 Å, c = 6.195 Å), as was determined by XRD and TEM [[i]]
[i]A.Keys, S.G.Bott, A.R.Barron*, Chem.Mater., 1999, 11(12), p.3578–3587, DOI:10.1021/cm9903632