Ion-beam-induced epitaxial crystallization of Si due to diffusion of point defects from crystalline and amorphous regions to the interphase boundary

Abstract

Ion-beam-induced epitaxial crystallization (IBIEC) of Si is studied on near-surface and buried amorphous layers. Nuclear losses of stimulating Ne+ ions take place completely either in the crystalline or in the amorphous part of the samples at a certain distance from the interphase boundary. The flow of point defects to the boundary both from amorphous and crystalline regions is found to be sufficient for phase transitions. In the crystalline Si at variation of the distance between the boundary and the maximum of nuclear losses within ≈ 100 nm the IBIEC rate remains proportional to the energy losses, while in amorphous material an increase in this distance essentially reduces the rate. When creating mobile point defects in amorphous Si the activation energy of IBIEC is about 0.24 eV in the target temperature range of 150 to 400°C. The obtained results are explained assuming an important role of high local defect concentrations in the displacement spikes of the ions. [Russian Text Ignored]