AVS 47th International Symposium
    Electronics Tuesday Sessions
       Session EL+NS-TuM

Paper EL+NS-TuM8
Molecular Arrays and Individual Dopants Studied by Ultrahigh Vacuum Scanning Tunneling Microscopy

Tuesday, October 3, 2000, 10:40 am, Room 312

Session: Molecular Electronics
Presenter: L. Liu, University of Illinois
Authors: L. Liu, University of Illinois
J. Yu, University of Illinois
N. Viernes, University of Illinois
M.C. Hersam, University of Illinois
N.P. Guisinger, University of Illinois
J.W. Lyding, University of Illinois
Correspondent: Click to Email
One aspect of molecular electronics is the fabrication of atomically precise molecular arrays on silicon substrates. Feedback controlled lithography (FCL) is used in conjunction with UHV STM to create atomically precise templates for molecular adsorption. Cobalt phthalocyanine (CoPc) molecules have been sublimed onto these templates and subsequently imaged in the STM. The difference between filled state and empty state images is explained. Current imaging tunneling spectroscopy (CITS) of CoPc is also performed and discussed. CoPc Molecular symmetry as well as the feature associated with the central Co atom are studied in all STM images. CITS has also been used to identify and study individual dopants on or near Si(100)2X1:H surfaces. For high quality UHV H-passivated Si(100) the Fermi level is unpinned at the surface, thus enabling the observation of subtle features including subsurface dopants. For example, boron atoms appear as slight hillocks in filled state images and as centro-symmetric depressions in empty states. Full CITS data sets and their analysis and interpretation will be presented. The same techniques will be used to present results for isolated Si dangling bonds created by FCL.