Cathodoluminescence microscopy and spectroscopy of n-type 4H-SiC epilayers C. Díaz-Guerra and J. Piqueras Eur. Phys. J. Appl. Phys., 27 1-3 (2004) 227-230 Published online: 15 July 2004 DOI: 10.1051/epjap:2004091