Structural, Electrical and Optical Properties of Ternary Al_2xIn_2(1-x)O₃ Films Prepared by Metal Organic Chemical Vapor Deposition

Abstract:

New wide band gap semiconductors with tunable properties are desperately needed to meet the ever-increasing demands of photoelectric devices operating in the ultraviolet (UV) or even deep ultraviolet (DUV) region. In this study, the ternary aluminum indium oxide (Al_2xIn_2(1-x)O₃) films with different Al compositions of x [Al/(Al+In) atomic ratio] were successfully grown on the α-Al₂O₃ (0001) substrates at 650 °C by metal organic chemical vapor deposition (MOCVD). The influence of Al content on the structural, compositional, electrical and optical properties of the obtained films was investigated in detail. The structural transition from polycrystalline structure of bixbyite In₂O₃ to amorphous was observed as the Al content increased. The lowest resistivity of 1.52×10^-3 Ω·cm was obtained for the sample with x=0.2, along with the respective hall mobility and carrier concentration values of 12.87 cm²V^-1s^-1 and 2.27×10²⁰ cm^-3. The average visible transmittances of over 83% were demonstrated for all the samples. The calculated values of optical band gap for the films indicated continuous increase from 3.82 to 5.88 eV as the x value increased from 0.1 to 0.9. The Al_2xIn_2(1-x)O₃ films with tunable properties may be potentially employed in the fabrication of transparent optoelectronic devices, such as UV detectors, transparent TFTs and short wavelength light-emitting devices.

• Periodical: Materials Science Forum (Volume 898)
• Pages: 1796-1803
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.898.1796
• Online since: June 2017
• Authors: Xue Jian Du, Xian Jin Feng*, Wei Guang Wang, Cai Na Luan, Jin Ma
• Keywords: Al_2xIn_2(1-x)O₃ Films, Band-Gap Modulation, MOCVD, Photoelectric Properties

References

[1] Ü. Özgür, Y.I. Alivov, C. Liu, A. Teke, M.A. Reshchikov, S. Doğan, V. Avrutin, S.J. Cho, H. Morkoç, A comprehensive review of ZnO materials and devices, J. Appl. Phys. 98 (2005) 041301.

DOI: 10.1063/1.1992666

[2] S. Nakagomi, T. -a. Sato, Y. Takahashi, Y. Kokubun, Deep ultraviolet photodiodes based on the β-Ga2O3/GaN heterojunction, Sensor. Actuat. A Phys. 232 (2015) 208-213.

DOI: 10.1016/j.sna.2015.06.011

[3] Z. Liu, D. Zhang, S. Han, C. Li, T. Tang, W. Jin, X. Liu, B. Lei, C. Zhou, Laser ablation synthesis and electron transport studies of tin oxide nanowires, Adv. Mater. 15 (2003) 1754-1757.

DOI: 10.1002/adma.200305439

[4] S. Yoshida, S. Misawa, S. Gonda, Properties of AlxGa1-xN films prepared by reactive molecular beam epitaxy, J. Appl. Phys. 53 (1982) 6844-6848.

DOI: 10.1063/1.329998

[5] W. Shan, J. Ager III, K. Yu, W. Walukiewicz, E. Haller, M. Martin, W. McKinney, W. Yang, Dependence of the fundamental band gap of AlxGa1-xN on alloy composition and pressure, J. Appl. Phys. 85 (1999) 8505-8507.

DOI: 10.1063/1.370696

[6] W. Yang, S. Hullavarad, B. Nagaraj, I. Takeuchi, R. Sharma, T. Venkatesan, R. Vispute, H. Shen, Compositionally-tuned epitaxial cubic MgxZn1-xO on Si(100) for deep ultraviolet photodetectors, Appl. Phys. Lett. 82 (2003) 3424.

DOI: 10.1063/1.1576309

[7] S. Kumar, V. Gupte, K. Sreenivas, Structural and optical properties of magnetron sputtered MgxZn1-xO thin films, J. Phys. Condens. Mat. 18 (2006) 3343-3354.

DOI: 10.1088/0953-8984/18/13/002

[8] Z.G. Yang, L.P. Zhu, Y.M. Guo, Z.Z. Ye, B.H. Zhao, Preparation and band-gap modulation in MgxNi1−xO thin films as a function of Mg contents, Thin Solid Films 519 (2011) 5174-5177.

DOI: 10.1016/j.tsf.2011.01.082

[9] Y.H. Kwon, S.H. Chun, H.K. Cho, Controllable band-gap engineering of the ternary MgxNi1−xO thin films deposited by radio frequency magnetron sputtering for deep ultra-violet optical devices, Thin Solid Films 529 (2013) 417-420.

DOI: 10.1016/j.tsf.2012.06.021

[10] C. Li, D. Zhang, S. Han, X. Liu, T. Tang, C. Zhou, Diameter-controlled growth of single-crystalline In2O3 nanowires and their electronic properties, Adv. Mater. 15 (2003) 143-146.

DOI: 10.1002/adma.200390029

[11] H. Wu, D. Lu, K. Zhu, G. Xu, H. Wang, Crystalline and electronic structure of epitaxial γ-Al2O3 films, Physica B 413 (2013) 105-108.

[12] R. Hill, Energy-gap variations in semiconductor alloys, J. Phys. C Solid State Phys. 7 (1974) 521-526.

DOI: 10.1088/0022-3719/7/3/009

[13] F. Yang, J. Ma, X. Feng, L. Kong, Structural and photoluminescence properties of single-crystalline In2O3 films grown by metal organic vapor deposition, J. Cryst. Growth 310 (2008) 4054-4057.

DOI: 10.1016/j.jcrysgro.2008.06.075

[14] Y.G. Wang, S.P. Lau, H.W. Lee, S.F. Yu, B.K. Tay, X.H. Zhang, H.H. Hng, Photoluminescence study of ZnO films prepared by thermal oxidation of Zn metallic films in air, J. Appl. Phys. 94 (2003) 354-358.

DOI: 10.1063/1.1577819

[15] J. Du, L. Huang, Z. Chen, D.J. Kang, A controlled method to synthesize hybrid In2O3/Ag nanochains and nanoparticles: surface-enhanced Raman scattering, J. Phys. Chem. C. 113 (2009) 9998-10004.

DOI: 10.1021/jp811131t

[16] H.Y. Yu, M.F. Li, B.J. Cho, C.C. Yeo, M.S. Joo, D.L. Kwong, J.S. Pan, C.H. Ang, J.Z. Zheng, S. Ramanathan, Energy gap and band alignment for (HfO2)x(Al2O3)1-x on (100) Si, Appl. Phys. Lett. 81 (2002) 376-378.

DOI: 10.1063/1.1492024

[17] D. Zhang, H. Ma, Scattering mechanisms of charge carriers in transparent conducting oxide flms, Appl. Phys. A. 62 (1996), 487-492.

DOI: 10.1007/bf01567122

[18] X. Yu, J. Ma, F. Ji, Y. Wang, X. Zhang, H. Ma, Influence of annealing on the properties of ZnO: Ga films prepared by radio frequency magnetron sputtering, Thin Solid Films 483 (2005) 296-300.

DOI: 10.1016/j.tsf.2005.01.013

[19] S. Salam, M. Islam, A. Akram, Sol-gel synthesis of intrinsic and aluminum-doped zinc oxide thin films as transparent conducting oxides for thin film solar cells, Thin Solid Films 529 (2013) 242-247.

DOI: 10.1016/j.tsf.2012.10.079

[20] M. Ashokkumar, S. Muthukumaran, Microstructure and band gap tailoring of Zn0. 96-xCu0. 04CoxO (0≤x≤0. 04) nanoparticles prepared by co-precipitation method, J. Alloy. Compd. 587 (2014) 606-612.

DOI: 10.1016/j.jallcom.2013.10.246

[21] J. Liu, H. Deng, L. Zhu, K. Zhang, X. Meng, H. Cao, P. Yang, J. Chu, Structure, optical and magnetic properties of Bi1−xEuxFeO3 films fabricated by pulsed laser deposition, Appl. Surf. Sci. 316 (2014) 78-81.

DOI: 10.1016/j.apsusc.2014.07.179

[22] A. Taabouche, A. Bouabellou, F. Kermiche, F. Hanini, Y. Bouachiba, A. Grid, T. Kerdjac, Properties of cobalt-doped zinc oxide thin films grown by pulsed laser deposition on glass substrates, Mat. Sci. Semicon. Proc. 28 (2014) 54-58.

DOI: 10.1016/j.mssp.2014.05.024