INFLUENCE OF COPPER ON ELECTRICAL PROPERTIES OF 6H alpha -SiC.

Experiments to determine the influence of diffused Cu in 6H alpha -SiC, using an n-type sample doped with nitrogen and a p-type sample doped with boron, showed that in the case of the n-type sample the diffusion of copper increased the Hall coefficient indicating that the Cu behaved as an acceptor and that it compensated some of the nitrogen donors; in the p-type sample, before the diffusion, the Hall coefficient had a plateau at high temperatures; after the diffusion of copper the hole density was an order of magnitude higher and the plateau was not observed. Moreover, heating in the presence of copper reduced the slope of the temperature dependence R(T).