Effect of Atomic Oxygen and Electron Irradiation on the Electronic Structure of KTiOPO4 Crystal

KTiOPO4 (KTP) crystals are prepared by the top-seeded solution growth method. Effects of space irradiation on KTP crystal structure have been investigated using Space Tribology in-situ Analysis System: KTP crystal (001) surfaces were irradiated by atomic oxygen (AO) and electron (EL), and the electronic structure was analyzed using X-ray photoelectron spectroscopy (XPS). The AO has strong oxidizing property which results in decreases in the intensity of C 1s peak. The content of P increases after AO/EL irradiation, while the content of Ti decreases after AO irradiation. The reduced Delta BE (OP) shows stronger ionicity of PO bonds after AO/EL irradiation compared with pristine KTP crystal. The deconvolution of O 1s photoemission line reveals that peaks at 530.8-531.0 and 530.1 eV are assigned to OP and OTi bonds, respectively. Additionally, variations in the trend of OP bond and OTi bond contents are resembled to that of P and Ti after AO/EL irradiation.