[1] Wang Jun, Yu Junsheng, Li Lu, et al.Appl.Phys.Lett., 2008, 92:133308.

[2] Sedat N, Hilmi V D.Appl.Phys.Lett., 2009, 95: 151111.

[3] Lee Hyunkoo, Park Insun, Kwak Jeonghun, et al.Appl.Phys.Lett., 2010, 96: 153306.

[4] Zou Ye, Deng Zhenbo, L Zhaoyue, et al.J.Lumin., 2010, 130: 959.

[6] Hao Jingang, Deng Zhenbo, Yang Shengyi.Journal of Luminescence, 2007, 122-123: 723.

[8] Braun D, Heeger A.J.Appl.Phys.Lett., 1991, 58: 1982.

[9] Van Slyke S A, Chen C H, Tang C W.Appl.Phys.Lett., 1996, 69: 2160.

[10] Zhang Xiaowen, Li Jun, Zhang Liang, et al.Synth.Met., 2010, 160: 788.

[11] Jiang Xueyin, Zhang Zhilin, Cao Jin, et al.Solid-State Electron., 2008, 52: 952.

[12] Scott J C, Kaufman J H, Brock P J, et al.J.Appl.Phys., 1996, 79: 2745.

[13] Zhao D W, Sun X W, Jiang C Y, et al.Appl.Phys.Lett., 2008, 93: 083305.

[14] Chen P Y, Ueng H Y, Yokoyama M.J.Phys.Chem.Solids, 2010, 71: 922.

[15] Su S H, Yokoyama M, Li J F, et al.J.Electrochem.Soc., 2006, 153: H51.