Molecular Tools for Non-Planar Surface Chemistry
/ Authors
Taleana R Huff, Brandon Blue, Terry McCallum, Mathieu Morin, D. Allis, R. Addou, Jeremy Barton, Adam Bottomley, Doreen Cheng, Nina M. Ćulum
and 23 more authors
Michael Drew, Tyler Enright, A. Godfrey, Ryan Groome, Aru J. Hill, Alex Inayeh, Matthew R. Kennedy, R. J. Kirby, Mykhaylo Krykunov, Sam Lilak, Hadiya Ma, C. Mackie, O. MacLean, Jonathan Myall, Ryan Plumadore, Adam Powell, Henry Rodriguez, Luis Sandoval, Marc Savoie, Benjamin Scheffel, M. Taucer, Denis A. B. Therien, Duvsan Vobornik
/ Abstract
Scanning probe microscopy (SPM) investigations of on-surface chemistry on passivated silicon have only shown in-plane chemical reactions, and studies on bare silicon are limited in facilitating additional reactions post-molecular-attachment. Here, we enable subsequent reactions on Si(100) through selectively adsorbing 3D, silicon-specific"molecular tools". Following an activation step, the molecules present an out-of-plane radical that can function both to donate or accept molecular fragments, thereby enabling applications across multiple scales, e.g., macroscale customizable silicon-carbon coatings or nanoscale tip-mediated mechanosynthesis. Creation of many such molecular tools is enabled by broad molecular design criteria that facilitate reproducibility, surface specificity, and experimental verifiability. These criteria are demonstrated using a model molecular tool tetrakis(iodomethyl)germane ($Ge(CH_{2}I)_{4}$; TIMe-Ge), with experimental validation by SPM and X-ray photoelectron spectroscopy (XPS), and theoretical support by density functional theory (DFT) investigations. With this framework, a broad and diverse range of new molecular engineering capabilities are enabled on silicon.