Electronic current transport through alkoxy and alkyl monolayer‐based junctions is presented. Monolayers are prepared on n‐Si(100) with sufficiently high quality to reliably investigate the actual molecular effect of each monolayer on their current–voltage characteristics. The results show that extending the Si‐binding chemistry from alkene to alcohol is feasible, which should significantly facilitate preparation of monolayers with modified molecules.

Alkyl chain molecules on n-Si were used to test the concept of hybrid metal-organic insulator-semiconductor ͑MOIS͒ solar cells. Test structures were made by binding alkyl chain molecules via Si-O-C bonds to oxide-free n-Si surfaces, using self-assembly. With thiol groups at the terminals away from the Si, binding of Au nanoparticles, followed by electroless Au plating yields semitransparent top contacts. First cells give, under 25 mW/ cm 2 white light illumination, open-circuit voltage V oc = 0.48 V and fill factor FFϭ0.58. Because with sulfur termination the molecules have a dipole that limits inversion of the Si, we also used methyl-terminated monolayers. Even though then we can work, at this point, only with a Hg top contact, without chemical bond to the molecules, we get, using only radiation ͑ϳAM 1.5͒ collected around the contact, the expected higher V oc = 0.54 V, and respectable 0.8 FF, justifying further MOIS cell development.

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