Effect of variable temperature growth on the crystal quality and surface morphology characteristics of InGaAs/GaAs MQWs obtained via MOCVD

2021 ◽  
Author(s):  
Quhui Wang ◽  
Haizhu Wang ◽  
Jie Fan ◽  
Zhipeng Wei ◽  
Yonggang Zou ◽  
...  
Keyword(s):  
Surface Morphology ◽  
Variable Temperature ◽  
Crystal Quality ◽  
Temperature Growth ◽  
Morphology Characteristics

Preparation of InN by Means of AP-HCVD Using In Buffer Layers

2007 ◽  
Vol 1040 ◽  
Author(s):  
Hiroaki Yokoo ◽  
Naoki Wakiya ◽  
Naonori Sakamoto ◽  
Takato Nakamura ◽  
Hisao Suzuki
Keyword(s):  
Electrical Property ◽  
Surface Morphology ◽  
Buffer Layer ◽  
Atmospheric Pressure ◽  
Indium Nitride ◽  
Buffer Layers ◽  
Crystal Quality ◽  
X Ray Diffraction ◽  
X Ray ◽  
Quality Surface

AbstractWe have grown indium nitride (InN) films using In buffer layer on an a-plane sapphire substrate under atmospheric pressure by halide CVD (AP-HCVD). Growth was carried out by two steps: deposition In buffer layer at 900 °C and subsequent growth of InN layer at 650 °C. In order to compare, we also grown InN films on an a-plane sapphire. The InN films are investigated on crystal quality, surface morphology and electrical property using high-resolution X-ray diffraction (HR-XRD), X-ray pole figure, scanning electron microscope (SEM), Hall measurement. The results show that the crystal quality, surface morphology and electrical property of InN films are improved by using In buffer layer.

N-polar AlN nucleation layers grown by hot-wall MOCVD on SiC: Effects of substrate orientation on the polarity, surface morphology and crystal quality

2020 ◽  
Vol 580 ◽  
pp. 411819 ◽  
Author(s):  
Hengfang Zhang ◽  
Plamen P. Paskov ◽  
Olof Kordina ◽  
Jr-Tai Chen ◽  
Vanya Darakchieva
Keyword(s):  
Surface Morphology ◽  
Crystal Quality ◽  
Substrate Orientation

Improvement in surface morphology of GaSb buffer layer by two-step high and low temperature growth

2017 ◽  
Vol 477 ◽  
pp. 243-248 ◽  
Author(s):  
Shigekazu Okumura ◽  
Shuichi Tomabechi ◽  
Ryo Suzuki ◽  
Yusuke Matsukura ◽  
Koji Tsunoda ◽  
...  
Keyword(s):  
Low Temperature ◽  
Surface Morphology ◽  
Buffer Layer ◽  
Temperature Growth ◽  
Low Temperature Growth

Investigation of crystal quality and surface morphology of ZnTe:N epilayers grown on ZnTe and GaSb substrates

1994 ◽  
Vol 138 (1-4) ◽  
pp. 523-528 ◽  
Author(s):  
R.J. Miles ◽  
J.F. Swenberg ◽  
M.W. Wang ◽  
M.C. Phillips ◽  
T.C. McGill
Keyword(s):  
Surface Morphology ◽  
Crystal Quality

Effect of gas flow rate on surface morphology and crystal quality of ZnTe epilayers grown on GaAs substrates

2011 ◽  
Vol 46 (4) ◽  
pp. 551-554 ◽  
Author(s):  
Qixin Guo ◽  
Masaki Nada ◽  
Yaliu Ding ◽  
Katsuhiko Saito ◽  
Tooru Tanaka ◽  
...  
Keyword(s):  
Surface Morphology ◽  
Flow Rate ◽  
Gas Flow ◽  
Crystal Quality ◽  
Gas Flow Rate ◽  
Gaas Substrates

Improvement in Surface Morphology and Crystal Epitaxial CaF2 on Si (100) Through two Mbe Growth Stages

1988 ◽  
Vol 116 ◽  
Author(s):  
Yoshihiro Morimoto ◽  
Shoichiro Matsumoto ◽  
Shoji Sudo ◽  
Kiyoshi Yoneda
Keyword(s):  
Surface Morphology ◽  
Smooth Surface ◽  
Growth Stage ◽  
Early Growth ◽  
Crystal Quality ◽  
Growth Stages ◽  
Optimum Conditions ◽  
Si Substrate ◽  
Mbe Growth

AbstractWe report the first study on improvement in surface morphology and crystal quality of as—grown epitaxial CaF2 film on a (100) Si substrate grown through two MBE growth stages without any post-growth treatment. The degree of improvement in surfacemorphology and crystal quality depends not only on the thickness of an initial thin CaF2 film grown at the early growth stage of 550ºC but also on both the subsrate temperature and thickness of a sequential grown CaF2 film used for thesecond growth stage. Under optimum conditions, the CaF2 films exhibited high quality with an RBS/channeling minimum yield of 4%, together with a very smooth surface morphology without any other nuclel or cracks.

Research on the Surface Roughness Parameters of Micro-EDM

2013 ◽  
Vol 572 ◽  
pp. 281-286 ◽  
Author(s):  
Zhi Jie Chen ◽  
Ji Hong Shen ◽  
Yun Tao Dai
Keyword(s):  
Surface Roughness ◽  
Surface Morphology ◽  
Surface Topography ◽  
Evaluation Method ◽  
Micro Edm ◽  
Roughness Parameters ◽  
Surface Roughness Parameters ◽  
Evaluation Problem ◽  
Lubrication Characteristics ◽  
Morphology Characteristics

The surface topography errors of micro-EDM are mainly composed of surface roughness, surface waveness and so on. Research shows that the surface morphology provides a lot of useful information, which has serious influence on the friction and lubrication characteristics of the surface. However, for the micro-EDM surface topography evaluation problem, researchers have been using surface roughness parameters and evaluation method of mechanical process, which restrict the micro-EDM technology further development. On this account, the surface roughness parameters of micro-EDM have been deeply studied in this paper according to its technology characteristics and the surface morphology characteristics, therefore, the main researches and creative points are obtained, which the influence that the surface roughness of micro-EDM parts impact on their using performance is analyzed, and based on the surface morphology characteristics, some roughness evaluation parameters are given respectively according to peaks and valley, moreover, their numerical calculation are also gained.

scholarly journals Effects of Thermal Annealing on Optical Properties of Be-Implanted GaN Thin Films by Spectroscopic Ellipsometry

Crystals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 439
Author(s):  
Wenwang Wei ◽  
Jiabin Wang ◽  
Yao Liu ◽  
Yi Peng ◽  
Mudassar Maraj ◽  
...  
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Gallium Nitride ◽  
Thermal Annealing ◽  
Spectroscopic Ellipsometry ◽  
Communication Systems ◽  
Variable Temperature ◽  
Crystal Quality ◽  
Surface Decomposition

Wide bandgap III-V compounds are the key materials for the fabrication of short-wavelength optical devices and have important applications in optical displays, optical storage devices and optical communication systems. Herein, the variable-angle spectroscopic ellipsometry (SE) measurements are performed to investigate the thickness and optical properties of beryllium-implanted gallium nitride thin films that have been deposited on (0001) sapphire substrates by using low-pressure metalorganic chemical vapor deposition (LPMOCVD). The film layer details are described by using Parametric Semiconductor oscillators and Gaussian oscillators in the wavelength range of 200–1600 nm. The thickness, refractive indices and extinction coefficients of the Be-implanted films are determined at room temperature. Analysis of the absorption coefficient shows that the optical absorption edge of Be-implanted films changes from 3.328 eV to 3.083 eV in the temperature range of 300–850 K. With the variable temperature, Eg is demonstrated to follow the formula of Varshni. A dual-beam ultraviolet–visible spectrophotometer (UV–VIS) is used to study the crystal quality of samples, indicating that the quality of rapid thermal annealing (RTA) sample is better than that unannealed sample. By transport of ions in matter (TRIM) simulation and SE fitting the depths of Be implanted gallium nitride (GaN) films are estimated and in good agreement. The surface and cross-section morphologies are characterized by atomic force microscopy (AFM) and scanning electron microscope (SEM), respectively. The surface morphologies and thickness measurements of the samples show that RTA can improve crystal quality, while increasing the thickness of the surface roughness layer due to partial surface decomposition in the process of thermal annealing.

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