Anisotropic Effects in N+-Implanted LiNbO3

Abstract

A model of damage formation in LiNbO3 by N+ (150 keV, 300 K)‐implantation is discussed including the results of RBS, volume expansion, and refractive index investigation of simultaneously implanted, X‐, Y‐ and Z‐cuts. For dose values D italicN + ≦ 1 × 1015 cm−2 most of the displaced Nb atoms occupy vacant octahedral lattice sites. Because of the high stability of the crystal structure in the c‐direction, a complete amorphization of the implanted LiNbO3 layers is not attained even with D italicN + = 4 × 1016cm−2.

Annealing behavior of lithium niobate irradiated with He-ions at 100K

“…2(b)). This confirms the assumption that the different defect concentration measured by RBS channeling is a consequence of the preferential arrangement of displaced Nb-atoms on vacant octahedral sites [7,16]. Due to their position in the lithium niobate lattice these sites cause different dechanneling of the analyzing He-ions along different crystal axis.…”

Refractive index and absorption measurement in a thin layer by two reflection measurements

“…As a result of annealing at T, = 670 K the refractive index changes are reduced by nearly a factor of one half. The differences in the absolute values and in the profile of refractive index between the ordinary and extraordinary cases shown also here shall not be discussed because this has been done in our previous paper [ 7 ] . We want to concentrate our consideration on the influence of absorption.…”

Unveiling the Defect Structure of Lithium Niobate with Nuclear Methods

“…For irradiation, already the first systematic studies on ion implantation in LN by Jetschke et al [99] and Götz and Karge [100,101] showed a clear anisotropy in the generation of lattice defects. For irradiation with 150 keV N + ions at room temperature amorphization at the surface was reached with fluences of 5 × 10 15 cm −2 and 2 × 10 16 cm −2 for x-and y-cut material.…”