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UHV - Ambient Pressure RAIRS System
Our new high pressure RAIRS system contains two separate chambers for low and high pressure analysis. The main chamber is a typical UHV analysis chamber equipped with a quadrupole mass spectrometer (Prisma QMS200 from Pfeiffer), and a combined reverse-view low energy electron diffraction (LEED)- Auger electron spectrometer (AES) system from LK technologies (Series RVL2000). The two instruments share a common electron gun that is retractable for better positioning in the chamber. A CMA2000 electron energy analyzer is used for the AES experiments.The high pressure IR cell is located underneath the main chamber. It is equipped with a Bruker Vertex 70v FTIR; when performing a high pressure experiment, the crystal is passed through a differentially pumped sliding seal system into the high pressure cell. With the crystal at the IR focus, the sample probe seals off the upper UHV chamber from the high pressure IR cell.The low pressure in the main chamber is maintained by a turbo pump (Pfeiffer PM P02825), a titanium sublimation pump (Duniway TSP-275-00), and an ion pump (Varian 9192641M001).
RAIRS System
This chamber is equipped with an FTIR (Bruker IFS-66v/s) for RAIRS studies, a quadrupole mass spectrometer (Hiden HAL 201/3F) interfaced to a personal computer for temperature programmed desorption (TPD) studies, a single-pass cylindrical mirror analyzer (Physical Electronics Model no. 10-155), and LEED optics (Physical Electronics 15-180). It is pumped with a turbo-molecular pump (Leybold-Heraeus TMP 360) backed by a diffusion pump. It has all of the ancillary valves, vacuum gauges, sample manipulator, gas doser, sputter ion gun, etc., needed for surface science studies of reactive chemistry on transition metal surfaces.
UHV Scanning Probe Microscopy System
This variable temperature UHV Scanning Probe Microscopy system was manufactured by Omicron Nanotechnology GmbH (http://www.omicron.de/). It was purchased as a complete system and is equipped with a combined STM/AFM unit with a sample stage that permits images to be obtained, in principle, over the temperature range of 25 to 1500 K. The system is also equipped with a reverse view LEED instrument and with a metal evaporator. The STM uses a standard tube scanner with an electrochemically sharpened metal tip whereas AFM images are obtained with a needle-sensor based on a miniature quartz resonator. Sample introduction and tip exchange are achieved without breaking vacuum using a load lock system. The STM tip and AFM needle-sensor are readily interchangeable. The capabilities of the STM function of this instrument is demonstrated by images of the Si(111)-7x7 surface obtained by our group.
RAIR-XPS SystemIn addition to a dedicated FTIR (Mattson RS-10,000) for RAIRS studies, this chamber is equipped with reverse-view LEED optics (Princeton Research Instruments RVL 8-120), a quadrupole mass spectrometer (UTI Instruments 100C) that is fully computer controlled for multiplexed TPD studies, and a hemispherical electron energy analyzer (VG Scientific CLAM 2) and a dual Mg/Al anode X-ray source (VG Scientific) for XPS studies. The chamber is pumped by a turbo-molecular pump (Balzers TMP 520). The FTIR was purchased in 1984 from Mattson and has been upgraded with new electronics and software and is now controlled by a standard low cost personal computer. Although the RAIRS-2 chamber is completely independent of the separately described RAIRS-1 chamber, certain items such as IR detectors and polarizers are shared, to some extent.
Scanning Tunneling Microscopy SystemIn addition to a UHV STM, this chamber is equipped with
reverse-view LEED optics (Princeton Research Instruments RVL
8-120), a q
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