Ion-beam-induced crystal grain nucleation in amorphous silicon carbide

Ion-beam-induced crystallization (IBIC) was used to produce nanocrystals in the preamorphized region of a 6H-SiC bulk crystal. The precipitation was s timulated by high dose Al implantation at temperatures from 300 degrees C t o 700 degrees C. Using cross-sectional transmission electron microscopy (XT EM) and X-ray diffraction (XRD) under grazing incidence, the morphology of the nanocrystalline phase and its dependence on the implantation parameters were investigated. After IBIC the morphology of the recrystallized materia l completely differs from that after thermal crystallization. Randomly orie nted grains of 3C-SiC with almost spherical shape and mean diameters rangin g from 5 to 20 nm are formed during Al implantation. A critical ion dose fo r the onset of the recrystallization is found at about 1.9x10(16) Al+/cm(2) . (C) 2000 Elsevier Science B.V. All rights reserved.