Nuclear Instruments and Methods in Physics Research A 547 (2005) 56–63 High resolution HAXPES and status of the VOLPE project G. Panaccione a,Ã , G. Cautero b , A. Fondacaro c , M. Grioni d , P. Lacovig b , G. Monaco e ,F.Offi c , G. Paolicelli c , M. Sacchi f , G. Stefani c , P. Torelli f a INFM, TASC Laboratory, in Area Science Park, S.S.14, Km 163.5, I-34012 Trieste, Italy b Sincrotrone Trieste S.C.p.A., Lab. ELETTRA, in Area Science Park, S.S. 14 Km 163.5, I-34012 Trieste, Italy c INFM- Dipartimento di Fisica Universita’di Roma III, Via della Vasca Navale 84, I-00146 Roma, Italy d Ecole Polytechnique Federale (EPFL), CH-1015 Lausanne, Switzerland e European Synchrotron Radiation Facility, BP 220, F-38042 Grenoble, France f Laboratoire pour l’Utilisation du Rayonnement Electromagnetique LURE, Centre Univ. Paris Sud, BP34, 91898 Orsay Cedex, France Available online 9 June 2005 Abstract The status of the Volume PhotoEmission (VOLPE) project, now operational at ESRF, is reviewed. Commissioning phase and test experiments confirm that high energy resolution (71meV at 5934eV kinetic energy) with truly bulk sensitivity is achievable in Hard X-ray Photoelectron Spectroscopy (HAXPES) experiments. r 2005 Elsevier B.V. All rights reserved. PACS: 82.80.Pv; 71.20.Eh Keywords: High resolution PhotoElectron Spectroscopy; Electron analysers; Hard X-rays 1. Introduction Since the first experiment performed in the 1950’s by Siegbahn (Nobel prize in 1981) and co- workers, the PhotoElectron Spectroscopy (PES) technique (known with different acronyms XPS, ESCA, etc.) is one of the most powerful spectro- scopictoolstoinvestigateelectronicpropertiesand is characterised by strong surface sensitivity o1nm, an aspect fully exploited in the last four decades for studying the topmost atomic layers in solidsandinterfaces.However,thepresenceofthe surface, i.e. the reduced dimensionality and the brokensymmetrythatthesurfacerepresents,often prevents one from obtaining information on the bulk. Even at the highest electron kinetic energies normallyanalysed(upto2keV),thephotoelectron emission process is still surface sensitive, which turns into a limitation if bulk sensitivity is requested. Hard X-ray PhotoElectron Spectro- scopy (HAXPES) in the range 6–10keV is one of ARTICLE IN PRESS www.elsevier.com/locate/nima 0168-9002/$-see front matter r 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.nima.2005.05.012 Ã Corresponding author. Tel.: +390403758409; fax:+39040226767. E-mail address: panaccioneg@elettra.trieste.it (G. Panaccione).