Structural and electrical characterization of n(+)-type ion-implanted 6H-SiC

The influence of different annealing procedures on both structural and electrical characteristics is investigated for 6H-SiC implanted with nitrogen in the doping concentration range of 1x10(18)-1x10(20) cm(-3) by Transmission Electron Microscopy and Scanning Capacitance Microscopy. The poor electrical activation of N+ ions is correlated to the formation of a high density of precipitates in the implanted layer when increasing the doping concentration. A rapid thermal pre-annealing combined with conventional furnace annealing is effective to improve the active fraction but the presence of the precipitates overwhelms this effect for high doping concentration (>1x10(19) cm(-3)).