Abstract
We present the InxGa1-xN layers growth in a metalorganic chemical vapor deposition (MOCVD) system. First, we growth a GaN epitaxial layer on sapphire substrate, trimethylgallium (TMGa) and ammonia (NH3) are precursors of gallium and nitrogen, respectively, and hydrogen (H2) is used as the carrier gas. Later, on the GaN epilayer, the growth of the InxGa1- xN layer is carried out using trimethylindium (TMIn) as the indium precursor. The InxGa1-xN layers were studied using Xray diffraction (XRD) and scanning electron microscopy (SEM). XRD pattern shows the diffraction lines which could be ascribed to the formation of hexagonal In0.115Ga0.885N for sample A, and In0.26Ga0.74N for sample B, both with the wurtzite type structure. SEM images illustrate the effect of the growth pressure on the films surface morphology. At low pressure the sample A has smaller grain size and higher nuclei density; at high pressure the island size increases and has lower density (sample B). The alloy formation is favored at 550 Torr.References
N. A. El-Masry, E. L. Piner, S. X. Liu, S. M. Bedair Applied Physics Letters 72, 40 (1998).
X. L. Zhu, L. W. Guo, B. H. Ge, M. Z. Peng, N. S. Yu, J. F. Yan, J. Zhang, H. Q. Jia, H. Chen, and J. M. Zhou Applied Phys-ics Letters 91, 17211 (2007) 0.
A. Krost, and J. Bla Sing, H. Protzmann, M. Lunenburger, and M. Heuken Applied Physics Letters 76, 1395 (2000). determined by x-ray analysis, Applied Physics Letters 76 (2000) 1395.
Victor-Tapio Rangel-Kuoppa, Cesia Guarneros Aguilar, Victor Sánchez-Reséndiz, Structural, optical and electrical study of undoped GaN layers obtained by metalorganic chemical vapor deposition on sapphire substrates, Thin Solid Films 519 (2011) 2255.
C. Guarneros, V. Sanchez, GaN buffer layer growth by MOCVD using a thermodynamic non- equilibrium model, Vacuum 84 (2010) 1187.
P. Ruterana, G. Nouet, W. Van der Stricht, I. Moerman, and L. Considine, Chemical ordering in wurtzite InxGa1−xN layers grown on (0001) sapphire by metalorganic vapor phase epitaxy, Applied Physics Letters 72 (1998) 1742.
D. Doppalapudi, S.N. Basu, K.F. Ludwing, and T.D. Moustakas, Phase separation and ordering in InGaN alloys grown by molecular beam epitaxy, Journal of Applied Physics 84 (1998) 1389.
D. Doppalapudi, S.N. Basu, and T.D. Moustakas, Domain structure in chemically ordered InxGa1−xN alloys grown by molecular beam epitaxy, Journal of Applied Physics 85 (1999) 883.
M.K. Behbehani, E.L.Piner, S.X. Liu, N.A. El-Masry, and S.M. Bedair, Phase separation and ordering coexisting in InxGa1−xN grown by metal organic chemical vapor deposition, Applied Physics Letters 75 (1999) 2202.
B. Shen, Y. G. Zhou, Z. Z. Chen, P. Chen, R. Zhang, Y. Shi, Growth of wurtzite GaN films on a-Al2O3 substrates using light-radiation heating metal-organic chemical vapor deposition, Journal of Applied Physics A 68 (1999) 593.
O. Jani, C. Honsberg, Y. Huang, J-O Song, I. Ferguson, G. Namkoong, E. Trybus, A. Doolittle, S. Kurtz; Design, Growth, Fabrication and Characterization of High-Band GaP InGaN/GaN Solar Cells, Conference Record of the 2006 IEEE 4th World Conference on Photovoltaic Energy Conversion (IEEE,New York, 2006), V. 1 p. 20.
B. N. Pantha, J. Li, J. Y. Lin, H. X. Jiang, Single phase InxGa1-xN (0.25≤ x ≤ 0.63) alloys synthesized by metal organic chemical vapor deposition, Applied Physics Letters 93 (2008) 182107.
K. P. O’Donnell, J. F.W. Mosselmans, R. W. Martin, S. Pereira and M. E. White, Structural analysis of InGaN epilayers, Journal of Physics: Condensed Matter 13 (2001) 6977.
G. Xi, W. Hui, J. De-Sheng, W. Yu-Tian, Z. De-Gang, Z. Jian-Jun, L. Zong-Shun, Z. Shu-Ming, and Y. Hui, Evaluation of both composition and strain distributions in InGaN epitaxial film using x-ray diffraction techniques, Chinese Physic B 19 (2010) 106802.
M. Kurouchi, T. Araki, H. Naoi, T. Yamaguchi, A. Suzuki, and Y. Nanishi, Growth and properties of In-rich InGaN films grown on (0001) sapphire by RF-MBE, Physica Status Solidi (b) 241 (2004) 2843.
H. J. Kim, Y. Shin, Soon-Yong Kwon, H. J. Kim, S. Choi, S. Hong, C. S. Kim, Jung-Won Yoon, H. Cheong, E. Yoon, Compositional analysis of In-rich InGaN layers grown on GaN templates by metalorganic chemical vapor deposition, Journal of Crystal Growth 310 (2008) 3004.
Yen-Kuang Kuo, Bo-Ting Liou, Sheng-Horng Yen, Han-Yi Chu, Vegard’s law deviation in lattice constant and band gap bowing parameter of zincblende In1-xGaxN, Optics Communications 237 (2004) 363.
J. Wu, W. Walukiewicz, K. M. Yu, and J. W. Ager III, E. E. Haller, Hai Lu and William J. Schaff, Small band gap bowing in In1-xGaxN alloys, Applied Physics Letters 80 (2002) 4741.
C. Caetano, L.K. Teles, M. Marques, A. Dal Pino Jr., L.G. Ferreira, Phase stability, chemical bonds, and gap bowing of In1- xGaxN alloys: Comparison between cubic and wurtzite structures, Physical Review B 74 (2006) 045215.
N. K. van der Laak, R. A. Oliver, M. J. Kappers, C. McAleese and C. J. Humphreys, Stranski-Krastanov growth for InGaN/GaN: wetting layer thickness changes, Microscopy of Semiconducting Materials: Microscopy of Semiconducting Materials: Springer Proceedings in Physics 107 (2005) 13