Dielectric and pyroelectric properties of crystal ion sliced (CIS) LiNbO3 thin film

10 mum thick LiNbO3 crystal films have been fabricated from a poled bulk single crystal by the technique of Crystal Ion Slicing (CIS). The CIS technique is a promising approach to fabricate the free standing ferroelectric films for various integration applications and thin film structures. In this paper, the dielectric and pyroelectric properties of CIS LiNbO3 films as well as their temperature dependence were investigated in order to evaluate the ferroelectric properties of the films compared to the parent bulk single crystals. The investigation of the dielectric and pyroelectric responses were carried out in the temperature range of 30-100 degreesC. The results suggest that the film retains the ferroelectric properties of the bulk crystal with magnitudes close to those of single crystal values at room temperature. However, the virgin CIS film showed an additional distinct phase transition in the temperature range around 75 degreesC, as determined from the dielectric and pyroelectric responses. This phase transition does not exist in the original poled bulk crystal. The origin and the effect of thermal annealing on this phase transition are discussed in this paper.