Interaction of NF/sub 3/ with Ru(0001): Order at steps

Journal Article · Sun May 01 04:00:00 EDT 1988 · J. Vac. Sci. Technol., A; (United States)

DOI:https://doi.org/10.1116/1.575151· OSTI ID:5307141

Walczak, M M; Johnson, A L; Thiel, P A; Madey, T E

As part of a larger study of small fluorinated molecules on metal and semiconductor surfaces we investigated the adsorption of NF/sub 3/ on Ru(0001) using measurements of electron-stimulated desorption ion angular distribution (ESDIAD), low-energy electron diffraction (LEED), thermal desorption spectroscopy, and Auger electron spectroscopy (AES). At 100 K, NF/sub 3/ adsorbs with a high sticking probability. Some molecular NF/sub 3/ desorbs on heating, with a peak maximum at 200 K. All molecular desorption is complete by 400 K, but AES shows that nitrogen and fluorine remain on the surface up to 1100 K. The LEED pattern of the majority of the surface remains (1 x 1) at all coverages and annealing conditions. At most locations on the Ru(0001) surface (planar regions), ESDIAD is dominated by F/sup +/ emission normal to the surface over the temperature range 100--1100 K. On stepped regions of the surface (near edges and defects) highly directional and intense hexagonal patterns of F/sup +/ emission are observed (200--1100 K). The off-normal beams desorb at 67/sup 0/ +- 3/sup 0/ away from the normal. It appears that most ESDIAD patterns in this system are derived from F or NF/sub x/ (x<3) fragments.

• Research Organization: Surface Science Division, National Bureau of Standards, Gaithersburg, Maryland 20899 and Department of Chemistry and Ames Laboratory, Iowa State University, Ames, Iowa 50011
• OSTI ID: 5307141
• Journal Information: J. Vac. Sci. Technol., A; (United States), Journal Name: J. Vac. Sci. Technol., A; (United States) Vol. 6:3; ISSN JVTAD
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical &amp; Physicochemical Properties
ANNEALING
AUGER ELECTRON SPECTROSCOPY
CHEMICAL REACTIONS
CHEMISORPTION
COHERENT SCATTERING
DESORPTION
DIFFRACTION
ELECTRON DIFFRACTION
ELECTRON SPECTROSCOPY
ELEMENTS
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
HEAT TREATMENTS
HIGH TEMPERATURE
MEDIUM TEMPERATURE
METALS
NITROGEN COMPOUNDS
NITROGEN FLUORIDES
PLATINUM METALS
RUTHENIUM
SCATTERING
SEPARATION PROCESSES
SORPTION
SORPTIVE PROPERTIES
SPECTROSCOPY
SURFACE PROPERTIES
TRANSITION ELEMENTS
VERY HIGH TEMPERATURE