Challenges in the Synthesis and Processing of Hydrosilanes as Precursors for Silicon Deposition.

Hydrosilanes are highly attractive compounds, which can be processed as liquids with printing technology to amorphous silicon films on nearly any solid substrate. The silicon layers can be processed for electronic devices like transistors or thin-film solar cells. The endothermic character of hydrosilanes with their positive enthalpies of formation results in favorable properties for processing.

Syntheses and Molecular Structures of Liquid Pyrophoric Hydridosilanes.

Trisilane, isotetrasilane, neopentasilane, and cyclohexasilane have been prepared in gram scale. In-situ cryo crystallization of these pyrophoric liquids in sealed capillaries on the diffractometer allows access to the single crystal structures of these compounds. Structural parameters are discussed and compared to gas-phase electron diffraction structures from literature and with the results from quantum chemical calculations.

Synthesis and Properties of Branched Hydrogenated Nonasilanes and Decasilanes.

Branched higher silicon hydrides Si H with n > 6 were recently found to be excellent precursors for the liquid phase deposition of silicon films. Herein we report the gram-scale synthesis of the novel nona- and decasilanes (HSi)Si(SiH) Si(SiH) (2: n = 1, 5: n = 2) from (HSi)SiLi and Cl(SiPh) Cl by a combined salt elimination/dephenylation/hydrogenation approach. Structure elucidation of the target molecules was performed by NMR spectroscopy and X-ray crystallography.