ZnTe nanoparticles formed by ion implantation in a SiO2 layer on silicon

Ion implantation is a very simple and suitable way, compatible with the silicon technology, to form nanometric precipitates in materials. Sequential high dose (3-5 x 10(16) cm(-2)) implantations of tellurium and zinc ions have been performed in a 250 nm thick SiO2 layer thermally grown on (I 11) silicon. Their respective energies (180 and 104 keV) have been chosen to produce 5-10 at.% profiles overlapping at a mean depth of about 80 nm. Subsequent thermal treatments (800-1100 degreesC) lead to the formation of nanometric precipitates of the compound semiconductor ZnTe. Their size, crystalline structure and depth distribution have been studied as a function of annealing temperature using X-ray diffraction, transmission electron microscopy and Rutherford backscattering spectrometry. For the highest temperatures, the nanoparticles progressively redistribute in two bands located close to the surface and interface. Their mean diameter ranges between 13 and 26 nm, as a function of annealing temperature. (C) 2003 Elsevier B.V. All rights reserved.