Beamline 31 - Short information |
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Beamline 31 utilizes undulator radiation in the energy range 15 to 150 eV for scanning photoelectron microscopy with a lateral resolution in the one micrometer range. The instrument can be used to obtain chemical information from a surface either by recording photoelectron spectra from selected areas on the sample surface or by tuning the electron energy analyzer to a specific spectral feature and then scanning the sample to obtain an image showing the lateral distribution of this atomic species. The photon energy range and energy resolution are well suited for mesurements of valence bands and shallow core levels.
Contact persons:
Alexei Zakharov, beamline manager
Ulf Johansson
References:
U. Johansson, R. Nyholm, C. Törnevik and A. Flodström, Rev. Sci. Instrum. 66, 1398, 1995.
U. Johansson, Thesis, Department of Physics, Lund University, ISBN 91-628-2620-4, 1997.
Technical data:
| Source |
Undulator, period = 75 mm, 26 periods, Kmax = 1.8. |
| Monochromator |
PGM with two gratings (500 l/mm and 1000 l/mm) and K-B focusing optics. |
| Energy range |
15 - 150 eV. |
| Energy resolution |
E/dE = 600 - 1500. |
| Focusing optics |
Ring shaped ellipsoidal mirror with a demagnification factor of 30. |
| Photon flux on sample |
109 - 1010 ph/s. |
| Spot size on sample |
~ 1 µm. |
| Experimental station |
The system consists of separate analyzer and preparation chambers accessible via a transfer arm. The analyzer chamber, which also holds the ellipsoidal focusing mirror, is equipped with a hemispherical sector electron energy analyzer (VG CLAM2) and a piezo-driven sample scanning stage. The scanning range is 100 x 100 µm2 with an accuracy of < 0.5 µm. Coarse sample movements, ±3 mm, are made manually with micrometer screws. The preparation chamber is equipped with LEED, ion sputtering gun, sample storage magazine and a number of optional ports for user owned sample preparation accessories. |
2003-01-22
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