High electrical activation of aluminium and nitrogen implanted in 6H-SiC at room temperature by RF annealing

Al and N implantations were carried out in 6H-SiC n-type epitaxial layers at room temperature. RBS/C analysis confirms the presence of an amorphous layer up to the surface in the as-implanted samples. The samples rf-annealed at 1700 degreesC during 30 mn with a preliminary 40 degreesC per second heating slope are recrystallised in RBS/C analysis terms. SIMS measurements show no dopant loosing after the annealing and dopant profile distributions are in agreement with CNM Monte-Carlo simulation. A good surface stoichiometry is revealed by XPS after annealing but AFM surface measurements reveal a relatively high rns roughness (14 nm) on annealed samples. High electrical activation of dopants was found, 19 k Omega/square sheet resistance: which corresponds to 50 % electrical dopant activation for Al implanted layer, and 6.7 k Omega/square sheet resistance and 100% electrical activation for N-implanted layer.