Photoluminescence studies on MBE grown Co-doped ZnO thin films fabricated through ion implantation and swift heavy ion irradiation

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS

卷:272

Article; Proceedings Paper

Angadi, Basavaraj³  Kumar, Ravi²  Park, Dong-Hee¹  Choi, Ji-Won¹  Choi, Won-Kook¹ 

[1] Korea Inst Sci & Technol, Optoelect Mat Ctr, Seoul 130650, South Korea

[2] Interuniv Accelerator Ctr, New Delhi 110067, India

[3] Bangalore Univ, Dept Phys, Bangalore 560056, Karnataka, India

关键词: DMS;    ZnO;    Photoluminescence;    Swift heavy ion;   

DOI  :  10.1016/j.nimb.2011.01.088

来源: Elsevier

【 摘 要 】

The temperature dependant photoluminescence of the Co-doped ZnO thin films, prepared by ion implantation on the MBE grown ZnO thin films followed by swift heavy ion irradiation, were investigated. The phenomenon of negative thermal quenching (NTQ), where the photoluminescence (PL) intensity increases with temperature, in contrast to the usual behavior of decrease in intensity with temperature, has been observed. The I-3 peak and the peaks (a, 6, c, d, and e), corresponding to t(2g) and e(g) levels of the crystal field split Cod orbitals exhibit the NTQ behavior. The NTQ temperature range 35-45 K observed in un-doped ZnO shifts towards lower temperature with the Co doping. The increased number of dopant related and/or the vibrational/rotational resonance states with lower activation energies, from which the thermal excitation of the electrons takes place to the initial state of the PL transition, are responsible for the NTQ behavior. (C) 2011 Published by Elsevier B.V.

【 授权许可】

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