Synchrotron radiation glancing incidence X-ray diraction: a tool for structural investigations of ion implanted glasses Federico Zontone a, * , Francesco D'Acapito b , Francesco Gonella c a European Synchrotron Radiation Facility, BP220, F-38043 Grenoble Cedex, France b Consiglio Nazionale delle Ricerche, c/o ESRF ± GILDA CRG, BP220, F-38043 Grenoble Cedex, France c Dipartimento di Fisica, Universit  a di Padova, via Marzolo 8, I-35131 Padova, Italy Abstract The availability of very intense and highly collimated synchrotron radiation beams coupled with the glancing in- cidence geometry makes possible to study ion implanted glasses with X-ray diraction. We maximize the contribution to the scattering of the metal-rich (clusters) layer by working at the critical angle for total external re¯ection at the implanted layer-substrate interface. By using the refracted beam as a probe the diraction pro®le of the metallic clusters in very diluted samples (a single implant in the 10 16 at/cm 2 range) can be extracted. We report some results on SiO 2 glasses implanted with Cu and Ni. We used a very intense monochromatic 10(h) ´ 24(v) lm 2 beam from an undulator source. The data were collected by using an imaging plate (IP) system with integration times in the order of minutes. From the azimuthal integration of the images the clusters diraction pattern can be extracted enabling crystalline phases identi®cation, the retrieval of the lattice parameters and in some cases the determination of the clusters siz- es. Ó 1999 Elsevier Science B.V. All rights reserved. PACS: 61.10.-Lx; 61.46.+w; 81.60.Bn Keywords: X-ray diraction; Metallic clusters; Ion implantation 1. Introduction The low content of implanted material by means of the ion bombardment makes dicult to study such systems with X-rays. Structural inves- tigations of nanoparticles embedded in glass are routinely performed by electron microscopy tech- niques (Transmission Electron Microscopy, Mic- ro-Beam Electron Diraction). Here structural informations can be obtained even from a single particle but at the expense of a delicate and lengthy sample preparation. X-ray studies on diluted materials are mainly based on X-ray Absorption Spectroscopy (XAS), which probes the atomic environment of the ab- sorbing species. This technique gives only spherical averaged informations and the precision on the ®rst neighbors absolute distance is hardly below 0.02  A [1]. Nuclear Instruments and Methods in Physics Research B 147 (1999) 416±421 * Corresponding author. Tel.: +33 4 76 88 21 92; fax: +33 4 76 88 27 07; e-mail: zontone@esrf.fr 0168-583X/98/$ ± see front matter Ó 1999 Elsevier Science B.V. All rights reserved. PII: S 0 1 6 8 - 5 8 3 X ( 9 8 ) 0 0 5 6 9 - 2