本論文主要研究工作為利用鐵磁電極對有機高分子發光二極體造成自旋極化注入效應。藉由磁電導與磁電激發光的量測以及建立理論模型，間接地觀察到載子受到鐵磁電極的極化注入現象。首先，在實驗上，使用一常用的有機高分子綠光材料 G-PF (polyfluorene)作為發光主動層，並以PEDOT:PSS 和溴化四辛基銨(TOAB)分別作為電洞傳輸層和電子注入層，熱蒸鍍鋁Al作為陰極，觀察其在偏壓下的電場特性與大磁場下的磁場量測特性去探討其磁場效應的來源，進一步探討載子在元件內部的行為。再利用一鎳鐵合金作為電極，使得載子能夠被有效地極化注入發光層中經過傳輸和複合放光，量得其正磁電導效應的增加和負磁場效應減少。在小磁場下觀察到鎳鐵合金作為陽極的元件與鎳鐵合金的磁滯曲線的飽和磁場有相依關係，而且在磁電導有負向的磁場效應，認為載子不僅能有效自旋極化注入，還能做有效的自旋極化收集。而且藉由X光光電子能譜確認在陽極金屬與有機層介面有一氧化層，會因此造成反鐵磁偶合作用，產生負向磁場效應。因此，利用這些實驗結果提供我們在有機磁效應的模型機制解釋，間接印證了激發態機制和自旋極化注入的機制的可能性。

The main research in this paper is to explore the effect of spin-polarized injection in polymer light emitting diode by using ferromagnetic electrode. We indirectly observe spin-polarized carrier injection from the ferromagnetic electrode through the magnetoelectroluminescence and magnetoconductance measurement and the theoretical model. At first, we manufacture a light-emitting diode device by using G-PF(polyfluorene) to be emission layer, PEDOT:PSS and tetraoctylammnioum bromide(TOAB) as the hole transport layer and electron injection layer, then aluminum to be cathode. Furthermore, we analysis the electric field curve and magnetic field measurement data at high magnetic fields to figure out which component affect magnetic field effect, then discuss carrier behavior inside the device. In another way, we use Ni-Fe alloy as the electrode, and the carrier can be effectively polarized injected light-emitting layer and recombination, then we observe the increase of magnetoconductance ratio and the decrease of negative magnetic field effect of magnetoelectroluminescence. We observe some dependent relationship between the device with Ni-Fe alloy anode and the saturation magnetic field of the hysteresis curve of the Ni-Fe alloy, and the negative component of magnetoconductance. We thought the Ni-Fe alloy anode affect not only the spin polarized injection, but also the spin polarized collection. There is an oxide layer between anode and organic layer by using x-ray photoelectron spectroscopy measurement, and it cause antiferromagnetic coupling interaction result in negative magnetic field effect. Therefore, it is helpful to explain the mechanism of excited states from those experimental results, and provide confirmation of the excitation mechanism and the spin polarized injection mechanism.

[1] C. K. Chiang, C. R. Fincher, Jr., Y. W. Park, A. J. Heeger, H. Shirakawa, E. J. Louis, S. C. Gau, and A. G. Macdiarmid, Phys. Rev. Lett. 39, 1098 (1977).
[2] A. Köhler, J. S. Wilson, and R. H. Friend, Adv. Mater. 14, 701 (2002).
[3] R. H. Friend, R. W. Gymer, A. B. Holmes, J. H. Burroughes, R. N. Marks, C. Taliani, D. D. C.Bradley, D. A. Dos Santos, J. L. Bre das, M. LoÈ gdlund, and W. R. Salaneck, Nature 397, 121 (1999).
[4] M. Lenes, G. J. A. H. Wetzelaer, F. B. Kooistra, S. C. Veenstra, K. J. Hummelen, and P. W. M. Blom, Adv. Mater. 20, 2116 (2008).
[5] D. Mühlbacher, M. Scharber, M. Morana, Z. Zhu, D. Waller, R. Gaudiana, and C. Brabec, Adv. Mater. 18, 2884 (2006).
[6] D. Braga, and G. Horowitz, Adv. Mater. 21, 1473 (2009).
[7] J. Cornil, Jean-Luc Brédas, J. Zaumseil, and H. Sirringhaus, Adv. Mater. 19, 1791 (2007).
[8] M. N. Baibich, J. M. Broto, A. Fert, F. Nguyen Van Dau, and F. Petroff, P. Eitenne, G. Creuzet, A. Friederich, and J. Chazelas, Phys. Rev. Lett. 61, 2472 (1988).
[9] G. Binasch, P. Grunberg, F. Saurenbach, and W. Zinn, Phys. Rev. B 39, 4828 (1989).
[10] P. Grunberg, R. Schreiber, Y. Pang, M. B. Brodsky, and H. Sowers,
Phys. Rev. Lett. 57, 2442 (1986).
[11] U. E. Steiner, and T. Ulrich, Chem. Rev. 89,51 (1989).
[12] V. Ern, and R. E. Merrifield, Phys. Rev. Lett. 21,9 (1968).
[13] R. C. Johnson, and R. E. Merrifield, Phys. Rev. B 1,896 (1970).
[14] M. Pope, and C. E. Swenberg, Electric processes in organic crystals and polymers 2nd edition, Oxford university press, ISBN 978-0-19-512963-2 (1999).
[15] E. L. Frankevich, Chem. Phys. 297,315 (2004).
[16] V. Dyakonov, and E. Frankevich, Chem. Phys. 227,203 (1998).
[17] A. Kadashchuk, A. Vakhnin, I. Blonski, D. Beljonne, Z. Shuai, J. L. Brédas,
V. I. Arkhipov, P. Heremans, E. V. Emelianova, and H. Ba¨ssler, Phys. Rev. Lett. 93,066803 (2004).
[18] V. Dyakonov, G. Ro¨sler, M. Schwoerer, and E. L. Frankevich, Phys. Rev. B 56,3852 (1997).
[19] E.L. Frankevich, A. A. Lymarev, I. Sokolik, F. E. Karasz, S. Blumstengel, and H. H.Horhold, Phys. Rev. B 46, 9320 (1992).
[20] J. Kalinowski, Massimo Cocchi, D. Virgili, P. D. Marco, and V. Fattori, Chem. Phys. Lett. 380, 710 (2003).
[21] J. Kalinowski, J. Szmytkowski, and W. Stampor, Chem. Phys. Lett. 378, 380 (2003).
[22] Ö. Mermer, G. Veeraraghavan, T. L. Francis, Y. Sheng, D. T. Nguyen,
M. Wohlgenannt, A. Köhler, M. K. Al-Suti, and M. S. Khan, Phys. Rev. B 72, 205202 (2005)
[23] B. Hu and Y. Wu, Nature materials 6, 985 (2007).
[24] Z. H. Xu and B. Hu, Adv. Funct. Mater. 18, 1 (2008).
[25] B. Hu, L. Yan, and M. Shao, Adv. Mater. 21, 1500 (2009).
[26] M. Wohlgenannt and Z. V. Vardeny, J. Phys. Condens. Matter 15, R83 (2003).
[27] I. V. Tolstov, A.V. Belov, M. G. Kaplunov, I. K. Yakuschenko, N. G. Spitsina, M. M.Triebel, and E.L. Frankevich, J. Lumin. 112, 368 (2005).
[28] P. A. Bobbert, T. D. Nguyen, F. W. A. van Oost, B. Koopmans, and M. Wohlgenannt, Phys. Rev. Lett. 99, 216801 (2007)
[29] F. L. Bloom, W. Wagemans, M. Kemerink, and B. Koopmans,
Phys. Rev. Lett. 99, 257201 (2007).
[30] J. D. Bergeson, V. N. Prigodin, D. M. Lincoln, and A. J. Epstein,
Phys. Rev. Lett. 100, 067201 (2008).
[31] P. Desai, P. Shakya, T. Kreouzis, and W. P. Gillin, Phys. Rev. B 76, 235202 (2007).
[32] V. N. Prigodin, J. D. Bergeson, D. M. Lincoln, and A. J. Epstein, Synth. Met. 156,757 (2006).
[33] F. J. Wang, H. Ba¨ssler, and Z. V. Vardeny, Phys. Rev. Lett. 101,236805 (2008).
[34] N. Zettili, Quantum Mechanics Concepts and Applications, Wiley Press, New York (2001).
[35] S. Gasiorowicz, Quantum physics, 3rd edition, Wiley international Edition, Wiley Press, Hoboken (2003).
[36] D. J. Griffiths, Introduction to Quantum Mechanics, 2nd edition, Prentice Hall Press, Upper Saddle River (2005).
[37] R. Eisberg and R. Resnick, Quantum Physics of Atoms, Molecules, Solids, Nuclei, and Particles, 2nd edition, Wiley Press, New York (1985).
[38] W. Holzer, A. Penzkofer, and T. Tsuboi, Chem. Phys. 308, 93 (2005).
[39] Y. Wu and B. Hu, Appl. Phys. Lett. 89, 203510 (2006).
[40] A. P. Monkman, H. D. Burrows, L. J. Hartwell, L. E. Horsburgh, I. Hamblett, and S. Navaratnam, Phys. Rev. Lett. 86, 1358 (2001).
[41] A. Köhler and D. Beljonne, Adv. Funct. Mater. 14, 11 (2004).
[42] B. Brocklehurst, Nature 221,921 (1969).
[43] M. A. Baldo, S. Lamansky, P. E. Burrows, M. E. Thompson, S. R. Forrest,
Appl. Phys. Lett. 75, 4 (1999).
[44] M. A. Baldo, S. R. Forrest, Phys. Rev. B 62, 10958-10966 (2000).
[45] H. Ohkita, S. Cook, Y. Astuti, W. Duffy, S. Tierney, W. Zhang, M. Heeney, I. McCulloch, J. Nelson, D. D. C. Bradley, and J. R. Durrant, J. Am. Chem. Soc. 130,3030-3042 (2008).
[46] M. Segal, M. A. Baldo, R. J. Holmes, S. R. Forrest, and Z. G. Soos,
Phys. Rev. B 68, 075211 (2003).
[47] V. Dediu, M. Murgia, F. C. Matacotta, C. Taliani, and S. Barbanera,
Solid state communications 122, 181 (2002)
[48] E. Arisi, I. Bergenti, V. Dediu, M. A. Loi, M. Muccini, M. Murgia, G. Ruani, C. Taliani, and R. Zamboni, Journal of Applied Physics 93, 7682 (2003)
[49] Yue Wu, Bin Hu, Jane Howe, An-Ping Li and Jian Shen,
Physical Review B 75, 075413 (2007)
[50] C. L. Tsai, 有機高分子發光二極體的自旋極化注入效應, 國立成功大學物理研究所碩士論文,(2009)
[51] Sung-Nien Hsieh, Shih-Wei Hsiao, Tsan-Yao Chen, Chen-Yan Li, Chih-Hao Lee, Tzung-Fang Guo,Yao-Jane Hsu, Tsang-Lang Lin, Yen Wei and Ten-Chin Wen, J. Mater. Chem. 21, 8715 (2011)