The divalent organosilicon compounds (C5Me5)2Si (Cp*2Si) and (SiLN 2) have been compared concerning their reactivity toward metallocene derivatives of molybdenum and tungsten. While Cp*2Si does not react with Cp2MH2 (M = Mo, W), either thermally or photochemically, the reaction of SiLN 2 with Cp2MH2 leads via silanediyl insertion to Cp2M(H)(SiLN 2H) (M = Mo (1a), W (1b)). Irradiation of a mixture of Cp2Mo(PEt3) and Cp*2Si yields only decomposition products, whereas photolysis of equimolar amounts of Cp2Mo(PEt3) and SiLN 2 results in the formation of the silanediyl complex Cp2Mo(SiLN 2) (2). 2 is extremely moisture sensitive and easily adds one molecule of water to yield the metallosilanol Cp2Mo(H)(SiLN 2OH) (3). 1a and 2 have been characterized by X-ray crystallography. 2 is the first molybdenum silanediyl complex with a tricoordinated silicon atom. The silicon−molybdenum interaction in 2 has to be described as a dative bond from the silicon to the metal atom.

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The DEPx ,developed by OTB Solar, uses the ETP technique for the deposition of a silicon nitride ARC on silicon solar cells. With this technique very high deposition rates can be achieved and experiments were carried out with Shell Solar to investigate the quality of these ultra high-rate deposited silicon nitride layers. An optimization study which focused on mass density and thermal stability showed that mc-Si solar cell efficiencies of >15% can be reached with silicon nitride grown at >5 nmls.