Microscopy of Metal Oxide Surfaces

2000 ◽  
Vol 6 (4) ◽  
pp. 324-328
Author(s):  
Martin R. Castell ◽  
Sergei L. Dudarev ◽  
Christiane Muggelberg ◽  
Adrian P. Sutton ◽  
G. Andrew D. Briggs ◽  
...  

Abstract Elevated temperature scanning tunneling microscopy is used to study oxides that are room temperature insulators but become sufficiently electrically conducting at higher temperatures to allow imaging to be performed. Atomic resolution images of NiO, CoO, and UO2 have been obtained in this fashion which allow surface structure and defect determination. To complement the experiments, modeling of the electronic surface structure reveals which atomic sites give rise to the contrast observed in the images. Low voltage scanning electron microscopy is used to image small equilibrium pores in UO2 single crystals to evaluate the surface energy ratio of the (111) to (001) surfaces.

2000 ◽  
Vol 6 (4) ◽  
pp. 324-328 ◽  
Author(s):  
Martin R. Castell ◽  
Sergei L. Dudarev ◽  
Christiane Muggelberg ◽  
Adrian P. Sutton ◽  
G. Andrew D. Briggs ◽  
...  

AbstractElevated temperature scanning tunneling microscopy is used to study oxides that are room temperature insulators but become sufficiently electrically conducting at higher temperatures to allow imaging to be performed. Atomic resolution images of NiO, CoO, and UO2 have been obtained in this fashion which allow surface structure and defect determination. To complement the experiments, modeling of the electronic surface structure reveals which atomic sites give rise to the contrast observed in the images. Low voltage scanning electron microscopy is used to image small equilibrium pores in UO2 single crystals to evaluate the surface energy ratio of the (111) to (001) surfaces.


1993 ◽  
Vol 317 ◽  
Author(s):  
C.C. Umbach ◽  
J.M. Blakely

ABSTRACTEpitaxial Ge films (< 3 ML) have been grown at elevated temperatures on Si (001) grating substrates (repeat spacing of 2.0 μm) and imaged using room temperature scanning tunneling Microscopy (STM). The Ge films exhibit the 2×n reconstruction associated with missing dimer rows. The value of n and the growth morphology are influenced by the deposition rate and by annealing. At substrate temperatures of 600° C and deposition rates >0.5 ML/Min., islands elongated along the the dimer row direction nucleate at steps and on terraces. With sufficient annealing at 800° C, the islands coarsen and are eventually eliminated. The roughness of the A-type step becomes greater than that of the B-type step, which is the reverse of the situation with pure Si (001). The separation between missing dimer rows and hence the value of n are increased by annealing. Differences in substrate terrace widths due to the periodically varying step density of thegratings affect the growth Modes: two-dimensional islands occur near the extrema of the gratings whereas step flow occurs when steps are separated by ∼150 Å or less.


2013 ◽  
Vol 4 ◽  
pp. 927-932 ◽  
Author(s):  
Amir A Ahmad Zebari ◽  
Marek Kolmer ◽  
Jakub S Prauzner-Bechcicki

Islands composed of perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) molecules are grown on a hydrogen passivated Ge(001):H surface. The islands are studied with room temperature scanning tunneling microscopy and spectroscopy. The spontaneous and tip-induced formation of the top-most layer of the island is presented. Assistance of the scanning probe seems to be one of the factors that facilitate and speed the process of formation of the top-most layer.


2004 ◽  
Vol 108 (31) ◽  
pp. 11556-11560 ◽  
Author(s):  
Stefan J. H. Griessl ◽  
Markus Lackinger ◽  
Ferdinand Jamitzky ◽  
Thomas Markert ◽  
Michael Hietschold ◽  
...  

2017 ◽  
Vol 8 ◽  
pp. 1127-1134 ◽  
Author(s):  
Sebastian Schimmel ◽  
Zhixiang Sun ◽  
Danny Baumann ◽  
Denis Krylov ◽  
Nataliya Samoylova ◽  
...  

We performed a study on the fundamental adsorption characteristics of Er3N@C80 deposited on W(110) and Au(111) via room temperature scanning tunneling microscopy and spectroscopy. Adsorbed on W(110), a comparatively strong bond to the endohedral fullerenes inhibited the formation of ordered monolayer islands. In contrast, the Au(111)-surface provides a sufficiently high mobility for the molecules to arrange in monolayer islands after annealing. Interestingly, the fullerenes modify the herringbone reconstruction indicating that the molecule–substrate interaction is of considerable extent. Investigations concerning the electronic structure of Er3N@C80/Au(111) reveals spatial variations dependent on the termination of the Au(111) at the interface.


2019 ◽  
Vol 26 (06) ◽  
pp. 1850204
Author(s):  
HAO ZHENG ◽  
YONG XU ◽  
GUO-CAI DONG ◽  
JÖRG KRÖGER ◽  
RICHARD BERNDT

Room temperature scanning tunneling microscopy was used to investigate the adsorption of a dye molecule, iron-phthalocyanine (FePc), on ZnO(0001). Submolecular resolution reveals the orientation of molecules with respect to crystallographic directions of the surface. Upon adsorption, the molecular symmetry is reduced. First-principles calculations trace these observations to a strong molecule-substrate bond, which induces deformations of the molecule.


Sign in / Sign up

Export Citation Format

Share Document