連接層摻雜後的串聯有機發光二極體能夠在相同的電流密度下有效地提升元件的電流效率，適度地摻雜連接層可以提升連接層產生電流的能力。
本論文提供了較為直觀且簡單的元件方法驗證連接層是否產生載子，而這也是最接近串聯有機發光二極體的一種驗證方式。並且由實驗結果證明連接層除了有載子產生外，尚有載子累積在連接層P-N接面感應出內鍵電場，增強CGL分離載子的能力，而這兩種機制在連接層是並行的。
最後，用本實驗方法發現靠近陰極的Al-stack發光層對元件的電流效率貢獻度遠超過靠近陽極的ITO-stack。

Since doping in the connecting layer can improve the OLED current efficiency under the same current density efficiently , it is a good way to dope adequately in the connecting layer to improve the charge generation ability of the connecting layer.
In this study, we provide a simple and direct method to verify if the connecting layer could generate carrier or not under an undistorted way. As a result, the connecting layer can not only generate carrier, but carrier from electrodes to accumulate within the CGL and induce a build-in voltage to enhance charge generation, and both of the two mechanisms existed.
Finally, we find that the stack near the cathode (we called Al-stack) do more benefit to the tandem OLED device than the stack near the anode (we called ITO-stack) by this method.

[1] M. Pope, H. Kallmann, P. Magnante, J. Chem. Phys. 38 , p.2024(1963).
[2] J. H. Burroughes, D. D. C. Bradley, A. R. Brown, R. N. Marks, K. Mackay, R. H. Friend, P. L. Burns, and A. B. Holmes, Nature, 347 ,p.539 (1990).
[3] Y. Ohmore, and K. YoShino, Jap. J. Appl. Phys. 30, p.L938(1991).
[4] Y. Ohmore, and K. YoShino, Jap. J. Appl. Phys. 30, p.L941(1991).
[5] M. F. Lamorte and D. Abbort, Solid-State Electron. 22, 467(1979).
[6] J. K. Kim, E Hall, O. Sjolund, and L. A. Coldern, Appl. Phys. Lett. 74, 3251 ,(1999).
[7] X. Guo, G. D. Shen, G. H. Wang, W. J. Zhu, J. Y. Du, G. Gao, and D. S. Zou, Appl. Phys. Lett. 79, 2985 ,(2001).
[8] T. Matsumoto, T. Nakada, J. Endo, K. Mori, N. Kawamura, A. Yokoi, J. Kido, Peoceedings of IDMC’03,p.413, Fed. 18-21, (2003), Taipei, Taiwan.
[9] T. Matsumoto, T. Nakada, J. Endo, K. Mori, N. Kavamura,
A. Yokoi and J. Kido, SID Int. Symp. Dig. Tech. Pap., 34, 979(2003)
[10] T. Tsutsui and M. Terai, Appl. Phys. Lett. , 84, 440(2004).
[11] C. C. Chang, J. F. Chen, S. W. Hwang and C. H. Chen,
Appl. Phys. Lett., 87,p253501(2005).
[12] L. S. Liao, K. P. Klubek and C. W. Tang, Appl. Phys. Lett., 84,p167(2004).
[13] T. Y. Cho, C. L. Lin and C. C. Wu, Appl. Phys. Lett., 88, p111106(2006).
[14] M. K. Fung, K. M. Lau, S. L. Lai, C. W. Law, M. Y. Chan, C. S. Lee and S. T. Lee, J. Appl. Phys.,104, 034509(2008).
[15] S. L. Lai, M. Y. Chan, M. K. Fung, C. S. Lee, S.T. Lee , J. Appl.Phys,101, p014509 (2007).
[16] D. A. Neamen, Semiconductor Physics & Devices, 2nd Ed., p. 319.
[17] S. M. Sze, Physics of Semiconductor Devices (Wiley, New York, 1981).
[18] E. H. Rhoderick and R. H. Williams,
Metal-Semiconductor-Contacts (Clarendon, Oxford, 1988).
[19] A. J. Champbell and D. D. C. Bradley, J. Appl. Phys. 86, p.5004 (1999).
[20] I. H. Campbell, P. S. Davids, D. L. Smith, N. N. Barashkov,and J. P. Ferraris, Appl. Phys. Lett. 72, p.1863 (1998).
[21] P. S. Davids, I. H. Campell, and D. L. Smith, J. Appl. Phys. 82, p.6319 (1997).
[22] R. H. Fowler and L. Nordheim, Proc. R. Soc. London Ser. A 119, p.173 (1928).
[23] Y. Yang and A. J. Heeger, Appl. Phys. Lett. 64, p.1245 (1994).
[24] Y. Yang, E. Westerweele, C. Zhang, P. Smith, and A. J. Heeger, J. Appl. Phys. 77, p.694 (1995).
[25] H. Vestweber, J. Pommerehne, R. Sander, R. F. Mahrt, A. Greiner, W. Heitz, and H. Bässler, Synth. Met. 68, p.263 (1995).
[26] P. S. Davids, S. M. Kogan, I. D. Parker, and D. L. Smith, Appl. Phys. Lett. 69, p.2270 (1996).
[27] D. V. Khramtchenkov, H. Bässler, and V. I. Arkhipov, J. Appl. Phys. 79, p.9283 (1996).
[28] D. J. Pinner, R. H. Friend, and N. Tessler, J. Appl. Phys. 86, p.5116 (1999).
[29] P. E. Burrows, Z. Shen, V. Bulovic, D. M. McCarty, S. R. Forrest, J. A. Cronin, and M. E. Thompson, J. Appl. Phys. 79, p.7991 (1996).
[30] S. Karg, M. Meier, and W. Riess, J. Appl. Phys. 82, p.1951 (1997).
[31] A. J. Champbell, D. D. C. Bradley, and D. G. Lidzey, J. Appl. Phys. 82, p.6326 (1997).
[32] M. Dongge, I. A. Hümmelgen, B. Hu, and F. E. Karasz, J. Appl. Phys. 86, p.3181 (1999).
[33] Y. He and J. Kanicki, Appl. Phys. Lett. 76, p.661 (2000).
[34] D. Ma, I. A. Hümmelgen, X. Jing, Z. Hong, L. Wang, X. Zhao, F. Wang, and F. E. Karasz, J. Appl. Phys. 87, 312 (2000).
[35] K. C. Kao, W. Hwang, Electrical Transport in Solids
(Pergamon, Oxford, 1981).
[36] N. F. Mott and R. W. Gurney, Electronic Process in Ionic Crystals (Dover Publication, New York, 1940).
[37] W. Helfrich, Physics and Chemistry of the Organic Solid State 3, p.1 (1967).
[38] M. A. Lambert and P. Marks, Current Injection in Solids (Academic, New York, 1970).
[39] H. C. F. Martens, J. N. Huiberts, and P.W. M. Blom, Appl. Phys. Lett. 77, p.1852 (2000).
[40] P. W. M. Blom and M. C. J. M. Vissenberg, Mat. Sci. & Eng. 27, p.53 (2000).
[41] P. W. M. Blom, H. C. F. Martens, and J. N. Huiberts, Synth. Met. 121, p.1621 (2001).
[42] I. H. Campbell, D. L. Smith, C. J. Neef, and J. P. Ferraris, Appl. Phys. Lett. 74, p.2809 (1999).
[43] J. C. Scott, P. J. Brock, J. R. Salem, S. Ramos, G. G.
Mallianras, S. A. Carter, and L. Bozano, Synth. Met. 111-112, P.289 (2000).
[44] K. Unger, Phys. Stat, Sol. 2, p.1279 (1962).
[45] J. G. Simmons and M. C. Tam, Phys. Rev. B 7, p.3706 (1973).
[46] G. P. Owen, J. Sworakowski, J. M. Thomas, D. F. Williams, and J. O. Williams, J. Chem. Soc. Faraday II 70, p.853 (1974).
[47] A. J. Campbell, M. S. Weaver, D. G. Lidzey, and D. D. C. Bradley, J. Appl. Phys. 84, p.6737 (1998).
[48] M. Koehler, and I. A. Hümmelgen, J. Appl. Phys. 87, p.3074 (2000).
[49] S. B. Lee, K. Yoshino, J. Y. Park, and Y. W. Park, Phys. Rev. B 61, p.2151 (2000).
[50] C. C. Wu, J. K. M. Chun, P. E. Burrows, J. C. Sturm, M. E. Thompson, S. R. Forrest, and R. A. Register, Appl. Phys. Lett.66, p.653 (1995).
[51] G. Y. Jung, C. Pearson, L. E. Horsburgh, I. D. Samuel, A. P. Monkman, and M. C. Petty, J. Phys. D: Appl. Phys. 33, p.1029 (2000).
[52] L.S. Hung, L.R. Zheng, Appl. Phys. Lett.78, p.679 (2001).
[53] Y.Qiu, Y. Gao, L. Wang, Synth Met., 130, p.235 (2002)
[54] Z. B. Deng, X. M. Ding, S.T. Lee, Appl. Phys. Lett.74,
p.2222(1999).
[55] C. H. Chen, C. W. Tang, J. Shi, Thin Solid Films,
363, p.327 (2000)
[56] L. S. Liao, K. P. Klubek , C. W. Tang, Appl. Phys. Lett., 84, p.167 (2004).
[57]Chan-Ching CHANG, Shiao-Wen HUANG, Chin H. CHEN
and Jenn-Fang CHEN, Jap. J. Appl. Phys., 43, p6418-6422 (2004).
[58]Masaya TERAI, Katsuhiko FUJITA and Tetsuo TSUTSUI,
Jap. J. Appl. Phys., 44, pp.L 1059-L 1062 (2005).
[59]Michael Kröger,,Sami Hamwi,1 Jens Meyer,
1 Thomas Dobbertin, Thomas Riedl, Wolfgang Kowalsky,
and Hans-Hermann Johannes,Physical Review B, 75, 235321(2007)