Persistent photoconductivity in hydrogen ion-implanted KNbO3 bulk single crystal

33rd International Conference on the Physics of Semiconductors

Tsuruoka, R.^1 ; Shinkawa, A.^1 ; Nishimura, T.^1 ; Tanuma, C.^1 ; Kuriyama, K.^1 ; Kushida, K.^2

College of Engineering and Research Center of Ion Beam Technology, Hosei University, Tokyo, Koganei

184-8584, Japan^1

Department of Arts and Sciences, Osaka Kyoiku University, Kashiwara, Osaka

582-8582, Japan^2

关键词: Bulk single crystals;    Charge state;    Crystallinity degradation;    Hydrogen ions;    Ion fluences;    Ion implanted;    Perovskite structures;    Persistent Photoconductivity;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/864/1/012017/pdf
DOI  :  10.1088/1742-6596/864/1/012017

来源: IOP

【 摘 要 】

Persistent Photoconductivity (PPC) in hydorogen-ion implanted (001) oriented KNbO3bulk single crystals (perovskite structure at room temperature; ferroelectric with a band gap of 3.16 eV) is studied in air at room temperature to prevent the crystallinity degradation caused by the phase transition. Hydrogen is implanted into KNbO3bulk single crystals using the energy (the peak ion fluence) of 500 keV (5.0 × 1015cm-2). The resistivity varies from ∼108Ω/ for an un-implanted KNbO3sample to 2.3 × 105Ω/ for as-implanted one. suggesting the presence of donors consisting of hydrogen interstitial and oxygen vacancy. The PPC is clearly observed with ultraviolet and blue LEDs illumination rather than green and infrared, suggesting the release of electrons from the metastable conductive state below the conduction band relating to the charge states of the oxygen vacancy as observed in electron irradiated ZnO.