화학공학소재연구정보센터
Journal of Vacuum Science & Technology B, Vol.17, No.3, 1040-1044, 1999
B implantation in 6H-SiC: Lattice damage recovery and implant activation upon high-temperature annealing
Implantation of B into n-type 6H-SiC has been investigated. B ion implantation was performed in n-type 6H-SiC single crystals at room temperature and 500 degrees C. The implanted specimens were annealed at 1700 degrees C in SiH4 atmosphere. Lattice damage induced by implantation and its recovery was characterized by Raman scattering. The net boron concentration and the amount of damage created were predicted by TRIM simulations, The redistribution of the implanted atoms during high-temperature annealing was obtained by simulation of the diffusion process. Capacitance-voltage characteristics of Ni/6H-SiC Schottky barrier were numerically simulated assuming different boron incorporation lattice sites. The degree of p-type activation of B ions after annealing at 1700 degrees C was estimated to be in the range of 8%-15%. A compensation ratio of about 48% was determined. The conductivity type was not converted from n to p type. The comparison between the experimentally obtained dopant concentrations and those predicted by simulations shows that the concentration of the electrically active accepters is affected by outdiffusion of B due to the high annealing temperature of 1700 degrees C. Reduced damage compared with other ions implantation was observed. Recrystallization of the implanted material and absence of amorphous phases were detected after high-temperature annealing.