Deep level transient spectroscopy (DLTS) and capacitance-voltage (C-V) characteristics were used to investigate the effects induced by electron irradiation on the majority carrier traps in Schottky diodes prepared on 4H silicon carbide (SiC) epilayers grown by chemical vapor deposition (CVD). Electron beam induced current (EBIC) method was applied to measure the change in minority carrier diffusion length L related to the generation of traps by electron irradiation. Several energy levels were detected and their concentration monitored as a function of the irradiation dose. The correlation with the diode charge collection efficiency is also reported.