Optical and structural properties of AlN ceramics irradiated with heavy ions

Abstract

The paper presents the results of studying the effect of irradiation with 85 MeV Fe7+ ions on the optical and structural properties of nitride ceramics at an irradiation temperature of 300–1000 K. It has been established that a decrease in the intensity of absorption spectra is caused by appearance of defects, as well as an increase in impurity atoms, which lead to the substitution of Al and N atoms in the structure. The change in the average optical absorption reflects the balance between the annihilation of defects as a result of annealing at high temperatures and the processes of defect formation resulting from irradiation. An increase in the magnitude of absorption at high fluences indicates the predominance of defect formation processes as a result of the overlapping of ions and the resulting cascade defects over defects annealing. Moreover, at irradiation temperatures of 700 and 1000 K, a decrease in the density of dislocations and microdistortions is observed due to thermal annihilation of defects.