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.

Effects of SrAl2O4 Homo-Buffer Layer on SrAl2O4:Eu Phosphors Film Grown on Glass by RF Sputtering

2008 ◽  
Vol 368-372 ◽  
pp. 1358-1361 ◽  
Author(s):  
Xiao Yan Fu ◽  
Hiroshi Yamada ◽  
Chao Nan Xu
Keyword(s):  
Surface Morphology ◽  
Buffer Layer ◽  
Lattice Mismatch ◽  
Rf Sputtering ◽  
Buffer Layers ◽  
Preparation Technique ◽  
X Ray Diffraction ◽  
High Quality ◽  
Crystalline Film ◽  
X Ray

The influence of pre-deposition of homo-buffer layers on film quality is studied for SrAl2O4:Eu2+ (SAO) crystalline film prepared by RF magnetron method. This preparation technique is necessary to prepare high quality films suitable for the development of SAO devices. Crystallinity and surface morphology were characterized by X-ray diffraction and scanning electron microscopy. After introducing a homo-buffer layer, not only the crystalline but also the surface morphology and adhesion of the film were obviously improved. These results imply that the buffer layer relaxes the strain due to the lattice mismatch between SAO and quartz glass, which improved the crystalline and adhesion of the film.

Optimization of the carbonized buffer layer for the growth of high quality single crystal SiC on Si

2000 ◽  
Vol 640 ◽  
Author(s):  
T. Cloitre ◽  
N. Moreaud ◽  
P. Vicente ◽  
M. Sadowski ◽  
M. Moret ◽  
...  
Keyword(s):  
Atmospheric Pressure ◽  
Buffer Layers ◽  
Layer Surface ◽  
Cold Wall ◽  
X Ray Diffraction ◽  
High Quality ◽  
X Ray ◽  
Afm Imaging ◽  
Single Crystal Sic ◽  
Very High

ABSTRACTCarbonized buffer layers were formed on Si (100) nominally oriented substrates with propane diluted in palladium purified hydrogen in a cold wall vertical reactor. Subsequent SiC layers were grown using silane and propane at atmospheric pressure. The growth temperature was ranging from 1150°C to 1350°C. The layers obtained were characterized by LT photoluminescence, IR reflectivity, X-ray diffraction, micro-Raman on cleaved edges, AFM imaging, and optical microscopy. Drastic influence on the layer surface morphology was evidenced depending on the transition step between the carbonization and the SiC epitaxial growth. As a result, we have developed a carbonization process leading to very high quality 3CSiC films grown at 1250°C.

A Study of the Effect of Growth Rate and Annealing on GaN Buffer Layers on Sapphire

1995 ◽  
Vol 395 ◽  
Author(s):  
J.C. Ramer ◽  
K. Zheng ◽  
C.F. Kranenberg ◽  
M. Banas ◽  
S.D Hersee
Keyword(s):  
Growth Rate ◽  
Buffer Layer ◽  
Layer Growth ◽  
Buffer Layers ◽  
Degree Of Crystallinity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Gan Buffer Layer

ABSTRACTUsing atomic force microscopy (AFM) and X-ray diffraction (XRD) we have determined that on [0001] oriented sapphire, the GaN buffer layer shows a degree of crystallinity that is dependent on growth rate. Annealing studies show evolution of the crystallinity and the emergence of a preferred orientation. Also, substrate orientation is found to influence the buffer layer crystallinity. Based on this work and previous results, we propose that the GaN buffer layer growth can be described by the Stranski-Krastanov growth process.

Epitaxial Relationships and Electrical Properties of SrTiO3 Films on Various Thin -Fluoride/Si Structures

1994 ◽  
Vol 341 ◽  
Author(s):  
B. K. Moon ◽  
H. Ishiwara
Keyword(s):  
Buffer Layer ◽  
Buffer Layers ◽  
Breakdown Field ◽  
X Ray Diffraction ◽  
Dielectric Characteristics ◽  
X Ray ◽  
Si Substrates ◽  
Initial Stage ◽  
Growth Method ◽  
Step Growth

AbstractCrystalline strontium titanate (SrTiO3:STO) films were grown on Si(111) and Si(100) substrates using thin SrF2 and CaF2 buffer layers by two-step growth method. In all cases, fluoride buffer layers were effective in growing STO films on Si substrates, which is probably due to that fluoride buffer layers have excellent crystallinity and they can prevent formation of amorphous SiO2 layers on Si substrates at the initial stage of the STO deposition. It was found from X-ray diffraction and pole-figure measurements that (110)-oriented STO crystallites with three different positions to the substrate were grown on Si(111) substrates for both SrF2 and CaF2 buffer layers. In constrast, (100)-oriented STO films with 12-fold symmetry were grown on a SrF2/Si(100), and mixed (110)- and (100)-oriented STO crystallites were grown on a CaF2/Si(100) structure. It was concluded from these results that better crystallinity of STO films can be obtained on the SrF2 buffer layer in case of Si(111) and on the CaF2 buffer layer in case of Si(100). It was also found from I-V and C-V analyses that the STO films have good insulating and dielectric characteristics. For a SrTiO3 film on SrF2/Si(111) structure, the best values of breakdown field (at l.μA/cm2), resistivity (at IMV/cm) and dielectric constant were 2.3MV/cm, 8.2 × 1012 Ωcm and 72, respectively.

scholarly journals The Influence of Surface Morphology of Buffer Layer on the Critical Current Density in YBCO Coated Conductors

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Jie Xiong ◽  
Yudong Xia ◽  
Fei Zhang ◽  
Yan Xue ◽  
Kai Hu ◽  
...  
Keyword(s):  
Surface Morphology ◽  
Critical Current Density ◽  
Buffer Layer ◽  
Critical Current ◽  
Current Density ◽  
Coated Conductors ◽  
Buffer Layers ◽  
X Ray Diffraction ◽  
Ybco Films ◽  
Surface Morphologies

1 μm-thickYBa2Cu3O7-δ(YBCO) films were grown on the Y2O3/yttria stabilized zirconia (YSZ)/CeO2buffer layers with different surface morphologies using direct-current sputtering. The critical current density (Jc) value of YBCO was 1.1 MA/cm2when the root mean square surface roughness (Rrms) of the buffer layer was 2.5 nm. As theRrmsof the buffer layer increased to 15 nm, theJcdecreased to 0.3 MA/cm2. X-ray diffraction and scanning electron microscopy showed the strong relevance of the evolution of the structure and surface morphologies of YBCO films with the buffer layer of differentRrms. A model was proposed to explain the influence of surface morphology on the superconducting properties of YBCO films.

Twinning in epilayers of CdTe on Si: Influence of ZnTe buffer layer and substrate misorientation

1995 ◽  
Vol 399 ◽  
Author(s):  
A. Gray ◽  
N.K. Dhar ◽  
W. Clark ◽  
P. Charlton ◽  
J.H. Dinan ◽  
...  
Keyword(s):  
Molecular Beam Epitaxy ◽  
Buffer Layer ◽  
Molecular Beam ◽  
Buffer Layers ◽  
X Ray Diffraction ◽  
X Ray ◽  
Si Substrates

ABSTRACTX-ray diffraction spectra of CdTe epilayers grown with and without ZnTe buffer layers on <211> Si substrates by molecular beam epitaxy consist of 422 and 331 reflections. We interpret these as evidence for the existence of twins within the volume of a <211> oriented epilayer and show that twin volume is dependent on the ZnTe buffer layer and substrate misorientation.

Effects of CuIn0,5Ga0,5Se2 growth by isothermal and bithermal Cu-Poor/Rich/Poor sequence on solar cells properties

2009 ◽  
Vol 1165 ◽  
Author(s):  
Hakim Marko ◽  
Adam Hultqvist ◽  
Charlotte Platzer-Björkman ◽  
Sébastien Noël ◽  
John Kessler
Keyword(s):  
Solar Cells ◽  
Buffer Layer ◽  
Atomic Layer ◽  
Buffer Layers ◽  
X Ray Diffraction ◽  
Crystallographic Preferred Orientation ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Layer I

AbstractCo-evaporated CuIn0,5Ga0,5Se2 thin film solar cells were grown using a sequential Cu-Poor/Rich/Poor process (CUPRO). During the growth process, the substrate temperature was either kept constant at 570 °C (iso-CUPRO) or decreased during the first step to either 360 or 430 or 500 °C (bi-CUPRO). According to atomic force microscopy (AFM) measurements, the lower the temperature is in the first step the smoother the final CIGS surface becomes. By decreasing the first step temperature, cross-section scanning electron microscopy (SEM) and θ-2θ x-ray diffraction (XRD) do not reveal clearly any important changes of morphology and crystallographic preferred orientation. SLG/Mo/CIGS/Buffer layer/i-ZnO/ZnO:Al/grid(Ni/Al/Ni) solar cells with either a chemical bath deposited CdS or an atomic layer deposited Zn(O,S) buffer layer were fabricated. For both buffer layers, the bi-CUPRO processes lead to higher efficiencies. Besides, using Zn(O,S), the electronic collection was improved for the infrared spectrum as well as for the ultraviolet spectrum. This resulted in efficiencies close to 14,5% for the Zn(O,S) cells.

Effects of Annealing Treatment and Buffer Layer on Properties of ZnMgO Films Prepared on Diamond Substrates

2011 ◽  
Vol 311-313 ◽  
pp. 1205-1208
Author(s):  
Ke Tang ◽  
Lin Jun Wang ◽  
Jian Huang ◽  
Ji Jun Zhang ◽  
Wei Min Shi ◽  
...  
Keyword(s):  
Buffer Layer ◽  
Room Temperature ◽  
Annealing Treatment ◽  
Buffer Layers ◽  
Optical And Electrical Properties ◽  
X Ray Diffraction ◽  
Electrical Measurements ◽  
X Ray ◽  
Uv Visible

ZnMgO films were prepared at room temperature on freestanding diamond (FSD) substrates with and without ZnO buffer layers by radio-frequency (RF) reactive magnetron sputtering method. The effects of annealing treatment and ZnO buffer layers on the structural, optical, and electrical properties of the ZnMgO films were studied by X-ray diffraction (XRD), UV-visible spectrophotometer, and electrical measurements. The experimental results suggested that the annealing treatment and buffer layer were helpful to improve the crystalline quality of ZnMgO/diamond heteroepitaxial films.

Dynamical X-Ray Diffraction Analysis of Triple-Junction Solar Cells on Germanium (001) Substrates

2017 ◽  
Vol 26 (03) ◽  
pp. 1740011
Author(s):  
F. A. Althowibi ◽  
J. E. Ayers
Keyword(s):  
Solar Cells ◽  
Diffraction Analysis ◽  
Buffer Layer ◽  
Triple Junction ◽  
Lattice Mismatch ◽  
Buffer Layers ◽  
Threading Dislocation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Threading Dislocation Density

We demonstrate the dynamical x-ray diffraction analysis of metamorphic triple-junction solar cells grown on Ge (001) substrates. The solar cells investigated involve an In0.67Ga0.33P top cell, an In0.17Ga0.83As middle cell, and a Ge bottom cell. A graded buffer layer is inserted between the bottom and middle cells for the purpose of accommodating the lattice mismatch. Linearly-graded, step-graded, and S-graded compositional profiles were considered for this buffer layer. The x-ray rocking curve analysis for a number of hkl reflections including 004, 113, 116, 044, 026, and 117 was conducted for the case of Cu Kα1 radiation. We show that the use of non-destructive x-ray analysis allows determination of the threading dislocation densities in the top two cells. In the cases of S-graded or step-graded buffer layers, the buffer threading dislocation density could also be estimated.

A Study on the Growth of Cubic GaN Films Using an AlGaAs Buffer Layer Grown on GaAs (100) by Plasma-Assisted Molecular Beam Epitaxy

2000 ◽  
Vol 639 ◽  
Author(s):  
Ryuhei Kimura ◽  
Kiyoshi Takahashi ◽  
H. T. Grahn
Keyword(s):  
Molecular Beam Epitaxy ◽  
Buffer Layer ◽  
Molecular Beam ◽  
High Energy ◽  
Rf Plasma ◽  
Cubic Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cubic Gan

ABSTRACTAn investigation of the growth mechanism for RF-plasma assisted molecular beam epitaxy of cubic GaN films using a nitrided AlGaAs buffer layer was carried out by in-situ reflection high energy electron diffraction (RHEED) and high resolution X-ray diffraction (HRXRD). It was found that hexagonal GaN nuclei grow on (1, 1, 1) facets during nitridation of the AlGaAs buffer layer, but a highly pure, cubic-phase GaN epilayer was grown on the nitrided AlGaAs buffer layer.

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