6.0 mol. % ZnO doped LiNbO3 crystals were grown by Czochralski technique. V
arious Li/Nb mole ratios of 0.942, 0.970, 1.000, and 1.020 were used to pre
pare the starting materials. Second harmonic generation (SHG) experimental
results show that the phase matching temperature increases near linearly wi
th the increasing of Li/Nb ratio, and the SHG efficiency is enhanced by the
Zn doping and the increasing of Li/Nb ratio. The intrinsic and extrinsic d
efects are discussed in this paper to explain the SHG behavior and photo-da
mage resistance in the Zn doped Li-rich LiNbO3 crystals.