[21p-P8-1~5] 15.2 II-VI and related compounds

[21p-P8-5] Behavior of hydrogen in hydrogen-ion implanted KNbO₃ bulk single crystal: Evaluation by elastic recoil detection analysis

〇Ryotaro Tsuruoka¹, Akira Shinkawa¹, Tomoaki Nishimura¹, Chiaki Tanuma¹, Kazuo Kuriyama¹, Kazumasa Kushida² (1.Hosei Univ., 2.Osaka kyoiku Univ.)

Keywords:KNbO3,Ferroelectric material,H-ion implantation

Origins of low resistivity in H-ion implanted KNbO₃ bulk single crystals are studied by elastic recoil detection analysis (ERDA) and Van der Pauw methods. The H-ion implantation into KNbO₃ is performed using a 500 keV implanter. The ERDA experiment using the 1.5 MeV-⁴He⁺ beam can evaluate hydrogen from the surface to around 100 nm. The hydrogen concentration near the surface estimated using the 1.5 MeV helium beam is ~5.1×10¹⁴ cm^-2 for un-implanted KNbO₃ sample, ~5.6×10¹⁴ cm^-2 for as-implanted, ~3.4×10¹⁴ cm^-2 for 150°C annealed samples, respectively, indicating that a part of hydrogen is diffused out by annealing. The low resistive layer induced in H-ion implanted KNbO₃ suggests the existence of a shallow energy level related to the complex defect consisting of hydrogen interstitial and the proton induced defect such as oxygen vacancy.