Analysis of layer splitting in x and z-cut KTiOPO4 implanted by H+ ions

• Layer-splitting was achieved in H+-implanted x-cut and z-cut KTP.
• The influence from crystal orientation on layer splitting was discussed.
• The optimum ion fluence for layer splitting was determined.
• The temperature window for achieving layer exfoliation was investigated.

H+ ions with various fluences are implanted into x and z-cut KTP crystals to achieve KTP film. Post-implantation annealing under different temperature is imposed on the samples to induce layer splitting and surface morphology modification. Layer exfoliation is observed in freestanding z-cut samples. Layer splitting is obtained using bonding method in x-cut sample implanted with 117 keV H+ ions at ion fluence of 6 × 1016 ions/cm2. Optical microscopy, scanning electron microscope and atomic force microscopy are used to observe splitting phenomenon. Rutherford backscattering spectroscopy/channeling method is employed to measure lattice damage and to investigate the relationship between implantation-induced defects and layer splitting.