The radiation-induced defect formation in high purity 4H-SiC CVD epitaxial layers and changes in the electrical properties of diode structures based on its after irradiation with different fluences I MeV neutrons were investigated at temperatures as high as 700 K. The Z(1), deep center, typical for 4H-SiC, was observed both in the initial and irradiated samples. The presence and number of different deep levels increased with the neutron fluence. The rectifying properties of the diode structures disappeared after neutron irradiation with fluence of 6.2x10(14) cm(-2). However, the diode structures that had been degraded after irradiation with fast neutrons, recovered their properties at the temperature of 700 K.