Thiel Research Goup
STM: 5-fold icosahedral Al-Pd-Mn
Quasicrystal, 15 nm x 15 nm
STM: S/Ag(111) "dot-row" structure
0.1 ML at 200 K, 60 nm x 60 nm
LEED: clean NiAl(110)
165eV at 120 K
About Us
We try to understand real problems in corrosion, lubrication, heterogeneous catalysis and microelectronics (thin films) by creating simple model surfaces and studying their chemistry on an atomic scale. We then extrapolate this information back to the real system, where such knowledge is often unobtainable, either because of a lack of adequate experimental techniques or because of misleading extraneous factors. In order to create a simple model of a surface chemical process, we use single crystal surfaces with known morphology. Ultrahigh vacuum provides the well-controlled chemical environment necessary to study a reactive surface over a period of several hours. We can deliberately expose the sample to a chosen gas in order to change its surface composition and then characterize it.
There are two major projects currently underway in my group. These projects have all been selected because of their importance to fundamental and applied surface chemistry, and also because they are relatively new and unexplored. These two projects involve:
We primarily use scanning tunneling microscopy (STM) and low-energy electron diffraction (LEED) in our studies. Examples are shown to the left, at bottom and on the linked pages. We are very excited about our new X-ray photoelectron spectroscope (XPS).
STM:
Ag on Bulk Metallic Glass STM: Si 7x7
12 ML at 240 K, 250 nm x 250 nm 50 nm x 50 nm