Pulsed-dosing controls self-assembly: 1-Bromopentane on Si(111)-7×7

• Published in: Chemical physics letters Vol. 527; pp. 1 - 6
• Main Authors: Eisenstein, Alon, Harikumar, K.R., Huang, Kai, McNab, Iain R., Polanyi, John C., Zabet-Khosousi, Amir
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 27.02.2012
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/j.cplett.2011.12.052

Different patterns of bromination – one-per-corner-hole, or circles – on Si(111)-7×7 obtained by varying the dosing rate at room temperature. [Display omitted] ► High-pressure dosing with short pulses of gas has been combined with UHV STM. ► 1-Bromopentane physisorbed on Si(111), (a) one-per-corner-hole (OPCH), (b) circles. ► Localized reaction formed chemisorbed bromine-atoms, OPCH or circles. We have constructed a high-pressure fast-pulse dosing system for use with Scanning Tunneling Microscopy (STM). For 1-bromopentane on Si(111)-7×7 at low temperature (100K) two physisorbed phases were found to co-exist; spaced-out molecules above corner silicon-adatoms in a one-per-corner-hole (OPCH) pattern, and circles of molecules above middle-adatoms. By tuning the parameters of high-pressure fast-pulse dosing, we can choose which of these two patterns, OPCH or circles, to chemically imprint on room temperature silicon.