4H silicon carbide Schottky diodes were irradiated by 550 keV protons with the aim to place the ion range into the low-doped n-type epitaxial layer. The diodes were characterized using DLTS, C-V profiling and forward I-V curves. Calibration procedure of model parameters for device simulation has been carried out. It is based on modeling the doping compensation of the n-type epitaxial layer caused by the deep acceptor levels resulting from radiation damage. It is shown that the agreement of simulated and measured forward I-V curves of proton irradiated diodes can be achieved, if the profiles of deep levels are calibrated with respect to irradiation dose, the degradation of electron mobility due to charged deep levels is accounted of and the Schottky barrier height is properly adjusted. The proposed methodology introduces a starting point for exact calibration of ion irradiated SiC unipolar devices. (C) 2014 Elsevier Ltd. All rights reserved.