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

2021 ◽  
Quhui Wang ◽  
Haizhu Wang ◽  
Jie Fan ◽  
Zhipeng Wei ◽  
Yonggang Zou ◽  
2007 ◽  
Vol 1040 ◽  
Hiroaki Yokoo ◽  
Naoki Wakiya ◽  
Naonori Sakamoto ◽  
Takato Nakamura ◽  
Hisao Suzuki

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.

2020 ◽  
Vol 580 ◽  
pp. 411819 ◽  
Hengfang Zhang ◽  
Plamen P. Paskov ◽  
Olof Kordina ◽  
Jr-Tai Chen ◽  
Vanya Darakchieva

2017 ◽  
Vol 477 ◽  
pp. 243-248 ◽  
Shigekazu Okumura ◽  
Shuichi Tomabechi ◽  
Ryo Suzuki ◽  
Yusuke Matsukura ◽  
Koji Tsunoda ◽  

1994 ◽  
Vol 138 (1-4) ◽  
pp. 523-528 ◽  
R.J. Miles ◽  
J.F. Swenberg ◽  
M.W. Wang ◽  
M.C. Phillips ◽  
T.C. McGill

2011 ◽  
Vol 46 (4) ◽  
pp. 551-554 ◽  
Qixin Guo ◽  
Masaki Nada ◽  
Yaliu Ding ◽  
Katsuhiko Saito ◽  
Tooru Tanaka ◽  

1988 ◽  
Vol 116 ◽  
Yoshihiro Morimoto ◽  
Shoichiro Matsumoto ◽  
Shoji Sudo ◽  
Kiyoshi Yoneda

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.

2013 ◽  
Vol 572 ◽  
pp. 281-286 ◽  
Zhi Jie Chen ◽  
Ji Hong Shen ◽  
Yun Tao Dai

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.

Crystals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 439
Wenwang Wei ◽  
Jiabin Wang ◽  
Yao Liu ◽  
Yi Peng ◽  
Mudassar Maraj ◽  

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.

Sign in / Sign up

Export Citation Format

Share Document