Silylated gallium-sulfur ring systems as single source precursors to hexagonal gallium sulfide (GaS)

New single source precursors to hexagonal gallium sulfide (GaS) were investigated. Four organometallic compounds containing a Ga2S2 ring core, [R2Ga(μ-SSiR′3)]2 (R = Me, Et; R′ = Ph, iPr), were prepared and thermally decomposed to give chemically pure gallium sulfide. The decomposition temperatures as measured by TGA range from 200 to 350 °C and the resulting solid powders were found to be the hexagonal phase of GaS by XRD. The decomposition of the ethyl gallium derivatives were found to proceed by the initial loss of ethylene (TGA-EGA) followed by an unresolved second mode of decomposition to give hexagonal GaS. In contrast, the methyl gallium derivatives decomposed in one uniform stage to yield gallium sulfide. The precursors with isopropylsilyl groups were generally more volatile and decomposed at lower temperatures than the triphenylsilyl derivatives.