Journal Published Online: 01 July 2013
Volume 41, Issue 5

Stress State of GaN Epilayer Grown on Sapphire and 6H-SiC Substrates

CODEN: JTEVAB

Abstract

The stress states and influence of two opposite stress types under similar stress intensities on the structural and optical properties of GaN films grown on sapphire and 6H-SiC substrates via metalorganic chemical vapor deposition were investigated. The E2 (high) phonon shifts of Raman spectra show that tensile stresses exist in the GaN epilayer grown on 6H-SiC, whereas compressive stresses appear in the film grown on sapphire, indicating that the thermal mismatch between the epilayers and the substrates plays a major role in determining the residual stresses in GaN films. Narrower full widths at half-maximum of E2 (high) phonon and double crystal X-ray diffraction peaks and the higher E2 (high) phonon intensity are visible for the GaN film grown on sapphire, illustrating that under almost equivalent stress intensities, tensile stresses have a much more negative influence on the crystalline quality of GaN epilayers. Finally, a numerical relationship between the luminescent band gap and the biaxial stresses of the GaN films is obtained at 10 K.

Author Information

Zhang, Kexiong
School of Physics and Optoelectronic Engineering, Dalian Univ. of Technology, Dalian, CN
Liang, Hongwei
School of Physics and Optoelectronic Engineering, Dalian Univ. of Technology, Dalian, CN State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, CN
Song, Shiwei
School of Physics and Optoelectronic Engineering, Dalian Univ. of Technology, Dalian, CN
Yang, Dechao
State Key Laboratory on Integrated Optoelectronics, School of Electronic Science and Engineering, Jilin Univ., Changchun, CN
Shen, Rensheng
School of Physics and Optoelectronic Engineering, Dalian Univ. of Technology, Dalian, CN
Liu, Yang
School of Physics and Optoelectronic Engineering, Dalian Univ. of Technology, Dalian, CN
Xia, Xiaochuan
School of Physics and Optoelectronic Engineering, Dalian Univ. of Technology, Dalian, CN
Luo, Yingmin
School of Physics and Optoelectronic Engineering, Dalian Univ. of Technology, Dalian, CN
Du, Guotong
School of Physics and Optoelectronic Engineering, Dalian Univ. of Technology, Dalian, CN State Key Laboratory on Integrated Optoelectronics, School of Electronic Science and Engineering, Jilin Univ., Changchun, CN
Pages: 6
Price: $25.00
Related
Reprints and Permissions
Reprints and copyright permissions can be requested through the
Copyright Clearance Center
Details
Stock #: JTE20120231
ISSN: 0090-3973
DOI: 10.1520/JTE20120231