We present the growth of CaN epilayer on Si （111） substrate with a single A1GaN interlayer sandwiched between the GaN epilayer and A1N buffer layer by using the metalorganic chemical vapour deposition. The influence...We present the growth of CaN epilayer on Si （111） substrate with a single A1GaN interlayer sandwiched between the GaN epilayer and A1N buffer layer by using the metalorganic chemical vapour deposition. The influence of the AlN buffer layer thickness on structural properties of the GaN epilayer has been investigated by scanning electron microscopy, atomic force microscopy, optical microscopy and high-resolution x-ray diffraction. It is found that an A1N buffer layer with the appropriate thickness plays an important role in increasing compressive strain and improving crystal quality during the growth of AlGaN interlayer, which can introduce a more compressive strain into the subsequent grown GaN layer, and reduce the crack density and threading dislocation density in GaN film.展开更多
We investigate the influence of A1 preflow time on surface morphology and quality of AIN and GaN. The AIN and GaN layers are grown on a Si （111） substrate by metal organic chemical vapor deposition. Scanning electro...We investigate the influence of A1 preflow time on surface morphology and quality of AIN and GaN. The AIN and GaN layers are grown on a Si （111） substrate by metal organic chemical vapor deposition. Scanning electron microscopy, atomic force microscopy, x-ray diffraction and optical microscopy are used for analysis. Consequently, we find significant differences in the epitaxial properties of AlN buffer and the GaN layer, which are dependent on the AI preflow time. A1 preflow layers act as nucleation sites in the case of AiN growth. Compact and uniform AIN nucleation sites are observed with optimizing A1 preflow at an early nucleation stage, which will lead to a smooth AIN surface. Trenches and AlN grain clusters appear on the AIN surface while meltoback etching occurs on the GaN surface with excessive A1 preflow. The GaN quality variation keeps a similar trend with the AIN quality, which is influenced by AI preflow. With an optimized duration orAl preflow, crystal quality and surface morphology of AIN and GaN could be improved.展开更多
GaN films grown on(111)Si substrate with different lattice parameters of the AlN buffer layer by metal–organic chemical vapor deposition are studied.The stress states obtained by different test methods are compared a...GaN films grown on(111)Si substrate with different lattice parameters of the AlN buffer layer by metal–organic chemical vapor deposition are studied.The stress states obtained by different test methods are compared and it is found that the lattice parameter of the AlN buffer layer may have a significant effect on the stress state in the initial stage of subsequent GaN film growth.A larger compressive stress is beneficial to improved surface morphology and crystal quality of GaN film.The results of further orthogonal experiments show that an important factor affecting the lattice parameter is the growth rate of the AlN buffer layer.This work may be helpful for realizing simple GaN-on-Si structures and thus reducing the costs of growth processes.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 60506001,60476021,60576003,60776047and 60836003)the National Basic Research Program of China (Grant No. 2007CB936700)the Project of Technological Research and Development of Hebei Province,China (Grant No. 07215134)
文摘We present the growth of CaN epilayer on Si （111） substrate with a single A1GaN interlayer sandwiched between the GaN epilayer and A1N buffer layer by using the metalorganic chemical vapour deposition. The influence of the AlN buffer layer thickness on structural properties of the GaN epilayer has been investigated by scanning electron microscopy, atomic force microscopy, optical microscopy and high-resolution x-ray diffraction. It is found that an A1N buffer layer with the appropriate thickness plays an important role in increasing compressive strain and improving crystal quality during the growth of AlGaN interlayer, which can introduce a more compressive strain into the subsequent grown GaN layer, and reduce the crack density and threading dislocation density in GaN film.
基金Supported by the National Key Research and Development Program of China under Grant No 2016YFB0400200
文摘We investigate the influence of A1 preflow time on surface morphology and quality of AIN and GaN. The AIN and GaN layers are grown on a Si （111） substrate by metal organic chemical vapor deposition. Scanning electron microscopy, atomic force microscopy, x-ray diffraction and optical microscopy are used for analysis. Consequently, we find significant differences in the epitaxial properties of AlN buffer and the GaN layer, which are dependent on the AI preflow time. A1 preflow layers act as nucleation sites in the case of AiN growth. Compact and uniform AIN nucleation sites are observed with optimizing A1 preflow at an early nucleation stage, which will lead to a smooth AIN surface. Trenches and AlN grain clusters appear on the AIN surface while meltoback etching occurs on the GaN surface with excessive A1 preflow. The GaN quality variation keeps a similar trend with the AIN quality, which is influenced by AI preflow. With an optimized duration orAl preflow, crystal quality and surface morphology of AIN and GaN could be improved.
基金supported by Beijing Municipal Science&Technology Commission,Administrative Commission of Zhongguancun Science Park(Grant Nos.Z211100007921022 and Z211100004821001)the National Natural Science Foundation of China(Grant Nos.62034008,62074142,62074140,61974162,61904172,61874175,62127807,and U21B2061)+3 种基金Key Research and Development Program of Jiangsu Province(Grant No.BE2021008-1)Beijing Nova Program(Grant No.202093)Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB43030101)Youth Innovation Promotion Association of Chinese Academy of Sciences(Grant No.2019115).
文摘GaN films grown on(111)Si substrate with different lattice parameters of the AlN buffer layer by metal–organic chemical vapor deposition are studied.The stress states obtained by different test methods are compared and it is found that the lattice parameter of the AlN buffer layer may have a significant effect on the stress state in the initial stage of subsequent GaN film growth.A larger compressive stress is beneficial to improved surface morphology and crystal quality of GaN film.The results of further orthogonal experiments show that an important factor affecting the lattice parameter is the growth rate of the AlN buffer layer.This work may be helpful for realizing simple GaN-on-Si structures and thus reducing the costs of growth processes.
