JOURNAL OF ELECTRON SPECTROSCOPY and Related Phenomena ELSEVIER Journal of Electron Spectroscopy and Related Phenomena 70 (1994) 117-128 A very high resolution electron spectrometer N. Mktensson*, P. Baltzer, P.A. Briihwiler, J.-O. Forsell, A. Nilsson, A. Stenborg’, B. Wannberg Department of Physics, Uppsaia University, Box 530, S-75121 Uppsala, Sweden First received 8 April 1994; in final form 11 May 1994 Abstract The construction of a new electron energy analyzer for photoelectron spectroscopy is described. The analyzer is a full hemisphere with a mean radius of 200 mm. The spectrometer incorporates highly stable voltage supplies and is equipped with a multidetection system. The electron lens can be operated in different modes, optimizing transmission, spatial resolution or angular resolution. An angular resolution of better than 0.2” can be obtained. UV excited XeSp spectra recorded in the gas phase show that the energy resolution is better than 2.7 meV at 2 eV analyzer pass energy. Keywords: ESCA-200; Instrument; Novel; SES-200; UPS; XPS 1. Introduction A new electron energy analyzer primarily devel- oped for photoelectron spectroscopy such as X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS) and synchro- tron radiation experiments has been designed. It is a versatile analyzer which is also suitable for other sorts of experiments in which the energy of charged particles is analyzed. The development has been made in collaboration with Scienta Instru- ment AB who are now marketing the analyzer under the name SES-200. It is also part of their new ESCA-200 system. The analyzer was designed to fulfill the demands on a new XPSjUPS system for studying surfaces, ’ Permanent address: Scienta Instrument AB, Seminariegatan 33H, S-752 28 Uppsala, Sweden. * Corresponding author. size-selected deposited clusters and cluster-gas reactions. These applications put strong require- ments on the spectroscopy systems, e.g. in terms of combining high resolution with high trans- mission. The total system is going to be equipped with both an X-ray anode and a UV source. The analyzer system should therefore function as an optimized part of an XPS system and at the same time allow UPS studies at very high resolution. Synchrotron radiation applications also had to be accommodated in the design. An analyzer of this type will be included in the Uppsala beam-line under construction for the MAX II laboratory in Lund. MAX II is a dedicated third generation storage ring optimized for insertion devices. A number of additional requirements have been put on the spectrometer performance. First of all it should allow good access to the measurement posi- tion with various types of sample manipulators and excitation sources as well as the possibility to 0368-2048/94/$07.00 0 1994 Elsevier Science B.V. All rights reserved SSDZ 0368- 2048(94)02224- N