FORMATION AND CHARACTERIZATION OF COBALT 6H-SILICON CARBIDE SCHOTTKY CONTACTS

Rectifying Schottky contacts using e-beam evaporation of cobalt have been demonstrated on n-type silicon face 6H-SiC. Examination of the electrical properties was performed by I-V and C-V measurements as a function of annealing temperature in the 300-900-degrees-C range for 1 h. Excellent rectifying behavior was found up to 700-degrees-C. Heat treatments at 800-900-degrees-C formed different cobalt silicides (Co2Si and CoSi) containing homogeneously distributed carbon with carbon agglomerates at the surface. Consecutive annealings from 300 to 800-degrees-C increased the barrier height from 0.8 to 1.3 eV and the ideality factor from 1.15 to 1.46. Heat treatments at 900-degrees-C modified the contacts into an ohmic behavior.