TITLE

Compositional dependence of phase separation in InGaN layers

AUTHOR(S)
Rao, M.; Kim, D.; Mahajan, S.
PUB. DATE
September 2004
SOURCE
Applied Physics Letters;9/13/2004, Vol. 85 Issue 11, p1961
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Phase separation in InGaN layers grown by metalorganic chemical vapor deposition on GaN epilayers was investigated using transmission electron microscopy. Layer thicknesses of 220 and 660 nm were deposited with InN fractions ranging from 3% to 34%. At InN contents of 3%, plan-view TEM images show a homogeneous microstructure and selected area diffraction (SAD) patterns exhibit no evidence of satellite spots. InN contents of 12% result in a speckled contrast. Satellites close to the fundamental spots belonging to the wurtzite structure are present in SAD patterns and they are indicative of composition modulations lying in the (0001) growth plane. No satellites are observed along the [0001] direction, implying that phase separation is two-dimensional in nature. Samples containing InN fractions of between 22% and 28% have microstructures exhibiting much stronger contrast variations. Satellite spots in SAD patterns are further spaced from the fundamental reflections. This trend continues on increasing InN content to 34%. In addition, cross-sectional TEM images show an absence of contrast from InGaN layers with InN contents above 12%, in the vicinity of the InGaN/GaN interface, indicating that coherency strain inhibits phase separation. Arguments are developed to rationalize these observations.
ACCESSION #
14434610

 

Related Articles

  • Formation and optical properties of stacked GaN self-assembled quantum dots grown by metalorganic chemical vapor deposition. Hoshino, K.; Kako, S.; Arakawa, Y. // Applied Physics Letters;8/16/2004, Vol. 85 Issue 7, p1262 

    Multiple-layer stacked GaN quantum dots (QDs) with intense photoluminescence (PL) have been successfully grown by the Stranski-Krastanow growth mode in metalorganic chemical vapor deposition. Transmission electron microscopy (TEM) and scanning TEM analyses showed vertically aligned QDs resulting...

  • Near-diffraction-limited coherent emission from large aperture antiguided vertical-cavity surface-emitting laser arrays. Bao, Ling; Nam-Heon Kim, Ling; Mawst, Luke J.; Elkin, N. N.; Troshchieva, V. N.; Vysotsky, D. V.; Napartovich, A. P. // Applied Physics Letters;1/19/2004, Vol. 84 Issue 3, p320 

    We demonstrate that in-phase mode operation with a near-diffraction-limited beam can be realized in large aperture (up to 100 elements) antiguided vertical-cavity surface-emitting laser (VCSEL) arrays. A selective etching process with two-step metalorganic chemical vapor deposition is used for...

  • Stress evolution in nanocrystalline diamond films produced by chemical vapor deposition. Li, Hao; Sheldon, Brian W.; Kothari, Abhishek; Ban, Zhigang; Walden, Barbara L. // Journal of Applied Physics;11/1/2006, Vol. 100 Issue 9, p094309 

    Nanocrystalline diamond films were grown on silicon substrates by microwave plasma enhanced chemical vapor deposition with 1% methane, 2%–10% hydrogen, and argon. High resolution transmission electron microscope images and selected area electron diffraction patterns confirm that the films...

  • Theoretical and Experimental Study Towards Fabrication of Nanogap Dielectric Biosensor by Reversed Spacer Lithography. Hashim, U.; Shohini, M. E. A. // AIP Conference Proceedings;Mar2010, Vol. 1217 Issue 1, p505 

    A reversed spacer patterning technology using a sacrificial layer and a chemical vapor deposition (CVD) spacer layer has been developed, and is demonstrated to achieve sub-50 nm structures with conventional dry etching. The minimum-sized features are defined not by the photolithography but by...

  • Electrical and structural characterization of Mg-doped p-type Al0.69Ga0.31N films on SiC substrate. Chakraborty, Arpan; Moe, Craig G.; Wu, Yuan; Mates, Tom; Keller, Stacia; Speck, James S.; DenBaars, Steven P.; Mishra, Umesh K. // Journal of Applied Physics;3/1/2007, Vol. 101 Issue 5, p053717 

    We report on the electrical and structural characterization of Mg-doped Al-rich p-type Al0.69Ga0.31N alloys on SiC substrate grown by metal organic chemical vapor deposition. The impact of growth conditions and dopant activation annealing conditions on the electrical conductivity was...

  • Correlation of growth stress and structural evolution during metalorganic chemical vapor deposition of GaN on (111) Si. Raghavan, Srinivasan; Xiaojun Weng; Dickey, Elizabeth; Redwing, Joan M. // Applied Physics Letters;1/23/2006, Vol. 88 Issue 4, p041904 

    Compositionally graded AlGaN buffer layers enable the growth of thicker crack free layers of GaN on (111) Si than is possible with an AlN buffer layer. Using cross sectional transmission electron microscopy and in situ stress measurements, it is shown that a compressive growth stress is...

  • Infrared lasing in InN nanobelts. Hu, Ming-Shien; Hsu, Geng-Ming; Chen, Kuei-Hsien; Yu, Chia-Ju; Hsu, Hsu-Cheng; Chen, Li-Chyong; Hwang, Jih-Shang; Hong, Lu-Sheng; Chen, Yang-Fang // Applied Physics Letters;3/19/2007, Vol. 90 Issue 12, p123109 

    Infrared lasing from single-crystalline InN nanobelts grown by metal organic chemical vapor deposition was demonstrated. Transmission electron microscopy studies revealed that the InN nanobelts of rectangular cross section grew along [110] direction and were enclosed by ±(001) and...

  • Generation and behavior of pure-edge threading misfit dislocations in InxGa1-xN/GaN multiple quantum wells. Lü, W.; Li, D. B.; Li, C. R.; Zhang, Z. // Journal of Applied Physics;11/1/2004, Vol. 96 Issue 9, p5267 

    The relaxation of the misfit strain by the formation of misfit dislocations in InxGa1-xN/GaN multiple quantum wells grown by metal-organic chemical-vapor deposition was investigated by the cross-sectional transmission electron microscopy, double crystal x-ray diffraction, and...

  • Composition pulling effect and strain relief mechanism in AlGaN/AlN distributed Bragg reflectors. Liu, B.; Zhang, R.; Zheng, J. G.; Ji, X. L.; Fu, D. Y.; Xie, Z. L.; Chen, D. J.; Chen, P.; Jiang, R. L.; Zheng, Y. D. // Applied Physics Letters;6/27/2011, Vol. 98 Issue 26, p261916 

    We report on the composition pulling effect and strain relief mechanism in AlGaN/AlN distributed Bragg reflectors (DBRs) grown on GaN template/α-Al2O3(0001) by metal organic chemical vapor deposition. The reciprocal space mapping contours reveal that these DBRs are coherently grown....

Share

Read the Article

Courtesy of VIRGINIA BEACH PUBLIC LIBRARY AND SYSTEM

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics