ION-BEAM MODIFICATION OF SI SIC/SI LAYER SYSTEMS/

Buried, homogeneous silicon carbide (SiC) layers were formed in (100) and (111) silicon by ion beam synthesis (IBS). In order to study the i on beam induced epitaxial crystallization (IBIEC) of buried SiC layers , the carbide layers were amorphized by irradiation with 2 MeV Si2+ io ns at 300 K, followed by solid-phase epitaxial regrowth of surrounding amorphized silicon layers. IBIEC experiments were performed at 320 de grees and 600 degrees C using a 800 keV Si+ beam. It is shown by trans mission electron microscopy and electron diffraction that IBIEC works well on buried SiC layers and results in epitaxial recrystallization a t considerably lower target temperatures than necessary for thermal an nealing. The IBIEC process starts from both SiC/Si interfaces and may be accompanied by heterogeneous nucleation of poly-SiC as well as inte rfacial layer-by-layer amorphization, depending on irradiation conditi ons. The structure of the recrystallized regions in dependence of dose , dose rate, temperature and crystal orientation is described in detai l.