Ion beam synthesis of chromium silicide on porous silicon

Different types of porous Si layers several mu m thick were implanted with 170 keV Cr+ ions to fluences of 3 x 10(17) ions/cm(2) both at RT and 450 de grees C and then annealed (700 degrees C 90 min + 1000C degrees 15 min). Th e porous structure collapsed into a compact one as it was proved by the O r esonance method (Paszti et al.. 1998 [1]). The formed silicide compounds we re studied by Rutherford Backscattering Spectrometry (RBS), Glancing Incide nce X-ray Diffraction (GIXRD) and four point probe resistivity measurements . According to resonant RES and Elastic Recoil Detection (ERD)-measurements . the light impurities were partially expelled from the forming silicide la yer. The resistivity, in spite of the remaining high impurity level. is sur prisingly low. The quality of the formed silicide layer depends on the orig inal impurity level as well as on the implantation temperature and annealin g. (C) 2000 Elsevier Science B.V. All rights reserved.