Etch Pits and Threading Dislocations in GaN Films Grown by Metal-Organic Chemical Vapor Deposition
LU Min1,2,3, CHANG Xin4, LI Zi-Lan1,2,3, YANG Zhi-Jian1,2,3, ZHANG Guo-Yi1,2,3, ZHANG Bei1,2,3
1National Key Laboratory for Artifial Microstructure and Mesoscopic Physics, Peking University, Beijing 100871
2Research Center for Wide-Band Semiconductor Materials, Peking University, Beijing 100871
3Institute of Condense State Physics and Material Physics, School of Physics, Peking University, Beijing 100871
4Center for Electron Microscopy, Health Science Center, Peking University, Beijing 100083
Etch Pits and Threading Dislocations in GaN Films Grown by Metal-Organic Chemical Vapor Deposition
LU Min1,2,3;CHANG Xin4;LI Zi-Lan1,2,3;YANG Zhi-Jian1,2,3;ZHANG Guo-Yi1,2,3;ZHANG Bei1,2,3
1National Key Laboratory for Artifial Microstructure and Mesoscopic Physics, Peking University, Beijing 100871
2Research Center for Wide-Band Semiconductor Materials, Peking University, Beijing 100871
3Institute of Condense State Physics and Material Physics, School of Physics, Peking University, Beijing 100871
4Center for Electron Microscopy, Health Science Center, Peking University, Beijing 100083
Abstract： High quality epitaxial GaN films on (0001) sapphire substrates were grown by a commercial metal-organic chemical vapor deposition system. The etch-pits and threading dislocations in GaN films is studied by a scaning electron microscope (SEM) and a transmission electron microscope (TEM). The SEM images of GaN films etched in mixed acid solution (H3PO4:H2SO4 = 1:3) and molten KOH exhibit notably different etching pit densities of 5 x 108/cm2 and 4 x 107/cm2, respectively, which probably indicate that more kinds of etching pits were revealed when etched in mixed acid solution (H3PO4:H2SO4 = 1:3). Cross section TEM of GaN films with different g vectors showed the portions of different threading dislocations. Theoretical calculation indicates that the lattice and thermal expansion coefficient mismatch may be the main origins of pure edge threading dislocations.
(Direct observation of dislocations and other defects (etch pits, decoration, electron microscopy, x-ray topography, etc.))
引用本文:
LU Min;;CHANG Xin;LI Zi-Lan;;YANG Zhi-Jian;;ZHANG Guo-Yi;;ZHANG Bei;. Etch Pits and Threading Dislocations in GaN Films Grown by Metal-Organic Chemical Vapor Deposition[J]. 中国物理快报, 2003, 20(3): 398-400.
LU Min, , CHANG Xin, LI Zi-Lan, , YANG Zhi-Jian, , ZHANG Guo-Yi, , ZHANG Bei,. Etch Pits and Threading Dislocations in GaN Films Grown by Metal-Organic Chemical Vapor Deposition. Chin. Phys. Lett., 2003, 20(3): 398-400.
2003, Vol. 20 
