Work Function Engineering of Functionally Graded ZnO+Ga2O3 Thin Film for Solar Cell and Organic Light Emitting Diodes Applications
ZnO+Ga2O3 functionally graded thin films (FGTFs)
were examined for their potential use as Solar cell and organic light
emitting diodes (OLEDs). FGTF transparent conducting oxides (TCO)
were fabricated by combinatorial RF magnetron sputtering. The
composition gradient was controlled up to 10% by changing the
plasma power of the two sputter guns. A Ga2O3+ZnO graded region
was placed on the top layer of ZnO. The FGTFs showed up to 80%
transmittance. Their surface resistances were reduced to < 10% by
increasing the Ga2O3: pure ZnO ratio in the TCO. The FGTFs- work
functions could be controlled within a range of 0.18 eV. The
controlled work function is a very promising technology because it
reduces the contact resistance between the anode and Hall transport
layers of OLED and solar cell devices.
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Jang, S. Y. Lee, Thin Solid Films 516, (2008) 1382.
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[6] R. Al Asmar, S. Juillaguet, M. Ramonda, A. Giani, P. Combette,
A.khoury, A. Foucaran, J. Cryst. Growth 275, (2005) 512.
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[8] H. H. Huang, S. Y. Chu, P. C. Kao, Y. C. Chen, Thin Solid Films 516,
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Shin, J. Nanosci. Nanotechnol. 7, (2007) 4021.
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Nanosci. Nanotechnol. 8, (2008) 4877
[12] S. B. Zhang, S. H. Wei, A. Zunger, Physica B 273-274 (1999) 976
[13] T. Minami, T. Miyata, T. Yamamoto, Surface and Coatings Technology
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[14] J. S. Kim, B. Lagel, E. Moons, N. Johansson, I. D. Baikie, W. R. Salaneck,
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[1] S. Prada, U. Martinez, G. Pacchioni, Physical Review, B 78, (2008)
235423.
[2] T. Minami, Semicond. Sci. Technol., 20 (2005) 35.
[3] S. I. Jun, T. E. McKnight, M. L. Simson, P. D. Rack, Thin Solid Films
476, (2005) 59.
[4] B. D. Ahn, J. H Kim, H. S. Kang, C. H Lee, S. H. Oh, K. W. Kim, G. E.
Jang, S. Y. Lee, Thin Solid Films 516, (2008) 1382.
[5] K. Tominaga, D. Takada, K. Sinmomura, H. Suketa, K. Takita, K. Murai,
T. Moriga, Vacuum, (2008) 1.
[6] R. Al Asmar, S. Juillaguet, M. Ramonda, A. Giani, P. Combette,
A.khoury, A. Foucaran, J. Cryst. Growth 275, (2005) 512.
[7] M. Miyazaki, K. Sato, A. Mitsui, H. Nishimura J. Non-Crystalline Solids
218, (2008) 323.
[8] H. H. Huang, S. Y. Chu, P. C. Kao, Y. C. Chen, Thin Solid Films 516,
(2008) 5644.
[9] G. S. Heo, S. J Hong, J. W. Park, I. H. Lee, B. H. Choi, J. H. Lee, D. C.
Shin, J. Nanosci. Nanotechnol. 7, (2007) 4021.
[10] S. J. Hong, G. S. Heo, J. W. Park, I.H. Lee, B. H. Choi, J. H. Lee, D. C.
Shin, J. Nanosci. Nanotechnol. 7, (2007) 4077.
[11] G. S. Heo, S. J Hong, J. W. Park, B. H. Choi, J. H. Lee, D. C. Shin, J.
Nanosci. Nanotechnol. 8, (2008) 4877
[12] S. B. Zhang, S. H. Wei, A. Zunger, Physica B 273-274 (1999) 976
[13] T. Minami, T. Miyata, T. Yamamoto, Surface and Coatings Technology
108, (1998) 583
[14] J. S. Kim, B. Lagel, E. Moons, N. Johansson, I. D. Baikie, W. R. Salaneck,
R. Friend, F. Cacialli, Synthetic Metals 111, (2000) 311.
@article{"International Journal of Chemical, Materials and Biomolecular Sciences:50376", author = "Yong-Taeg Oh and Won Song and Seok-Eui Choi and Bo-Ra Koo and Dong-Chan Shin", title = "Work Function Engineering of Functionally Graded ZnO+Ga2O3 Thin Film for Solar Cell and Organic Light Emitting Diodes Applications", abstract = "ZnO+Ga2O3 functionally graded thin films (FGTFs)
were examined for their potential use as Solar cell and organic light
emitting diodes (OLEDs). FGTF transparent conducting oxides (TCO)
were fabricated by combinatorial RF magnetron sputtering. The
composition gradient was controlled up to 10% by changing the
plasma power of the two sputter guns. A Ga2O3+ZnO graded region
was placed on the top layer of ZnO. The FGTFs showed up to 80%
transmittance. Their surface resistances were reduced to < 10% by
increasing the Ga2O3: pure ZnO ratio in the TCO. The FGTFs- work
functions could be controlled within a range of 0.18 eV. The
controlled work function is a very promising technology because it
reduces the contact resistance between the anode and Hall transport
layers of OLED and solar cell devices.", keywords = "Work Function, TCO, Functionally Graded Thin Films, Resistance, Transmittance.", volume = "6", number = "12", pages = "1126-3", }