Channeling irradiation of LiNbO3LiNbO3

Single crystals of x- and z  -cut LiNbO3LiNbO3 were irradiated using Si-ions with energies of 550 and 750 keV. The irradiation was carried out along the corresponding axial channel as well as at different tilt angles. The damage accumulation was investigated by means of Rutherford backscattering spectrometry (RBS). Due to the channeling of the ions, the damage distribution is shifted to larger depths if the irradiation is performed along low index crystallographic directions compared to that of an off-axis irradiation. Additionally, less damage is created by on-axis than by off-axis irradiation. Compared to the random irradiation with 550 keV Si-ions, the etched depth increases by a factor of 1.4 and 1.2 if the irradiation is carried out along the x- and the z-axis, respectively. From the dependence of the shift of the damage peak on the tilt angle a critical angle to avoid channeling of about 1.3° was determined for 750 keV Si-ions.