ION-BEAM-INDUCED AMORPHIZATION AND RECRYSTALLIZATION OF SI SIC/SI LAYER SYSTEMS/

Epitaxial, buried silicon carbide (SIG) layers have been fabricated in (100) and (111) silicon by ion beam synthesis (IBS). In order to stud y the ion beam induced epitaxial crystallization (IBIEC) of buried SiC layers, the resulting Si/SiC/Si layer systems were amorphized using 2 MeV Si2+ ion irradiation at 300 K. An unexpected high critical dose f or the amorphization of the buried layers is observed. Buried, amorpho us SiC layers were irradiated with 800 keV Si+ ions at 320 and 600 deg rees C, respectively, in order to achieve ion beam induced epitaxial c rystallisation. It is demonstrated that IBIEC works well on buried lay ers and results in epitaxial recrystallization at considerably lower t arget temperatures than necessary for thermal annealing. The IBIEC pro cess starts from both SiC/Si interfaces and may be accompanied by hete rogenous nucleation of poly-SiC as well as interfacial layer-by-layer amorphization, depending on irradiation conditions. The structure of t he recrystallized regions in dependence of dose, dose rate, temperatur e and crystal orientation is presented by means of TEM investigations.