Ion-implantation doping of crystalline 6H-SiC

The feasibility of ion implantation for p- and n-type doping of 6H-SiC has been studied. Single crystals were implanted at room temperature with 1017 ions/cm3 of B and Al, and of N and P, respectively, and step-annealed at temperatures up to 1900 K. The state of the crystal order was monitored by ion-beam-scattering techniques. After annealing at 1800 K, at a backscattering yield of about 1% in 〈0001〉-direction, maximum electrical activity of all dopants was observed within the range of 3–80% at room temperature. Impurity ionization levels were derived from conductivity measurements in the temperature range between 300–80 K, which also indicate the presence of compensating defects.