We have controllably modulated the drain current (I(D)) and threshold voltage (V(T)) in pseudo metal-oxide-semiconductor field-effect transistors (MOSFETs) by grafting a monolayer of molecules atop oxide-free H-passivated silicon surfaces. An electronically controlled series of molecules, from strong pi-electron donors to strong pi-electron acceptors, was covalently attached onto the channel region of the transistors. The device conductance was thus systematically tuned in accordance with the electron-donating ability of the grafted molecules, which is attributed to the charge transfer between the device channel and the molecules. This surface grafting protocol might serve as a useful method for controlling electronic characteristics in small silicon devices at future technology nodes.

Highlights d Sirt3 SUMOylation suppresses its catalytic activity in mitochondria d Fasting induces SENP1 translocation into mitochondria to de-SUMOylate Sirt3 d The SENP1-Sirt3 axis promotes fatty acid oxidation and energy production d Sirt3 SUMOylation mutation antagonizes HFD-induced obesity via energy expenditure

Work from several laboratories has shown that metal nauofilaments cause problems in some molecular electronics testbeds. A new testbed for exploring the electrical properties of single molecules has been developed to eliminate the possibility of metal nanofilament formation aud to ensure that molecular effects are measured. This metal-free system uses single-crystal silicon and single-walled carbon nauotubes as electrodes for the molecular monolayer. A direct Si-arylcarbon grafting method is used. Use of this structure with Jt-conjugated organic molecules results in a hysteresis loop with current-voltage measurements that are useful for an electronic memory device. The memory is non-volatile for more than 3 days, non-destructive for more than 1,000 reading operations and capable of more thau 1,000 write-erase cycles before device breakdown. Devices without Jt-conjugated molecules (Si-H surface only) or with long-chain alkylbearing molecules produced no hysteresis, indicating that the observed memory effect is molecularly relevant. Claims, 7 Drawing Sheets