Domain size, layer number and morphology control for graphene grown by chemical vapor deposition

2017 ◽  
Vol 10 (04) ◽  
pp. 1730003 ◽  
Author(s):  
Ruiwen Xue ◽  
Irfan H. Abidi ◽  
Zhengtang Luo
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Domain Size ◽  
Past Research ◽  
Production Methods ◽  
The Past ◽  
Number Of Layers ◽  
Size Number ◽  
Wide Range

Over the past a few years, high-quality graphene preparation has been evolved from low-yield micromechanical exfoliation in including a wide range of production methods, in particular by chemical vapor deposition (CVD). Here, we review the state-of-the-art on synthesis of graphene using CVD method and the strategies to control the graphene grain size, number of layers and morphology, mainly focusing on the graphene growth that uses Cu as substrate. We highlight the success of the past research in the field and provide a review of the methods that were used for such controlled synthesis.

Nanostructured Nickel Oxide Films Prepared by Chemical Vapor Deposition and Their Electrochromic Properties

2008 ◽  
Vol 8 (5) ◽  
pp. 2703-2706 ◽  
Author(s):  
J. R. Vargas Garcia ◽  
E. M. Lazcano Ugalde ◽  
F. Hernandez Santiago ◽  
J. M. Hallen Lopez
Keyword(s):  
Chemical Vapor Deposition ◽  
Nickel Oxide ◽  
Vapor Deposition ◽  
Near Infrared ◽  
Chemical Vapor ◽  
Optical Transmittance ◽  
Structural Features ◽  
Electrochromic Properties ◽  
Wide Range ◽  
Nio Films

The influence of the deposition conditions on the structural features and electrochromic properties of nickel oxide (NiO) films prepared by chemical vapor deposition has been investigated. NiO films have been prepared on fluorine doped tin oxide (FTO) coated glass substrates from nickel-acetylacetonate precursor and their electrochromic properties have been studied by cyclic voltammetry in a 0.1 M KOH solution at room temperature. Films exhibiting only the NiO phase were obtained at deposition temperatures higher than 450 °C in a wide range of reactor pressures (0.13 to 66.6 kPa). Particularly, NiO films prepared at 500–550 °C from 0.13 to 53.3 kPa are transparent in nature and exhibit a crystallite size varying from 10 to 60 nm. An appreciable anodic electrochromic change from transparent to black coloured resulted from a very porous surface morphology and film thickness of about 3.5 μm. The electrochromic change was maintained over 3000 switching cycles. Nanostructured 3.5 μm-thick NiO films showed a maximum difference in optical transmittance of about 40% in the near-infrared region. These results make the nanostructured NiO films comparables with those prepared by other deposition techniques.

The Effects of Hydrogen Flowrate during Pre-Annealing on Graphene Growth by Chemical Vapor Deposition Using Methanol as a Liquid Carbon Precursor

2019 ◽  
Vol 290 ◽  
pp. 107-112
Author(s):  
Raed Abdalrheem ◽  
Fong Kwong Yam ◽  
Abdul Razak Ibrahim ◽  
Khi Poay Beh ◽  
Hwee San Lim ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Light Transmittance ◽  
High Hydrogen ◽  
Flow Rates ◽  
Hydrogen Flow ◽  
Number Of Layers ◽  
Crystallite Sizes ◽  
Grown Graphene

Studying an influence of several parameters on Chemical Vapor Deposition (CVD) used for graphene synthesis is crucial to optimizing the graphene quality to be Compatible with advanced devices. The effect of different hydrogen (H2) flow-rates (0, 50, 100, 150, 200, 250, and 300 sccm) during the pre-annealing process on CVD grown graphene have been reported. This study revealed that hydrogen flow rates during annealing changed the surface roughness/smoothness of the copper substrates. For high hydrogen flow rates, the smoothing effect was increased. Furthermore, the annealed graphene samples emerged a deferent number of layers because of morphological surface changes. According to Raman D- to G-band intensity ratios (ID/IG), the graphene quality was influenced by the annealing hydrogen flowrate. The visible light transmittance values of the grown graphene samples confirmed a few number of layers (mono to seven-layer). Mostly, the samples which annealed under moderate hydrogen flow rates showed less defects intensities and higher crystallite sizes.

scholarly journals Fabrication of Micron Scale Magnetic Nickel Features by Selective Area Organometallic Chemical Vapor Deposition

1997 ◽  
Vol 475 ◽  
Author(s):  
D. Welipitiya ◽  
C. N. Borca ◽  
P. A. Dowben ◽  
I. Gobulukoglu ◽  
Hong Jiang ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Magnetic Measurements ◽  
Chemical Vapor ◽  
Gradient Force ◽  
Selective Area ◽  
Wide Range ◽  
Radiation Induced ◽  
Organometallic Chemical Vapor Deposition

AbstractWe demonstrate that it is possible to deposit a wide range of magnetic features, using photoassisted and electron radiation induced selective area organometallic chemical vapor deposition. Large arrays of identical micron to nano scale Ni features were deposited by these methods. Their magnetic properties were studied by alternating gradient force magnetometry as well as magnetic force microscopy. Our morphological and magnetic measurements show that the structures are spatially well defined, and the magnetic properties are related to the structural shapes of the features.

Medium-Range Order in a-Si:H Below and Above the Onset of Microcrystallinity

1999 ◽  
Vol 557 ◽  
Author(s):  
D.L. Williamson
Keyword(s):  
Chemical Vapor Deposition ◽  
Solar Cell ◽  
Substrate Temperature ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Range Order ◽  
Medium Range Order ◽  
Hydrogen Dilution ◽  
Wide Range ◽  
Medium Range

AbstractMedium range order (MRO) and the formation of microcrystallites in a-Si:H prepared by plasma-enhanced chemical vapor deposition (PECVD) and hot-wire chemical vapor deposition (HWCVD) have been probed by systematic x-ray diffraction studies with films as thin as those used in solar cells. Effects of substrate temperature, hydrogen dilution, film thickness, and type of substrate have been examined. High-hydrogen-diluted films of 0.5 μm thickness, using optimized deposition parameters for solar cell efficiency and stability, are found to be partially microcrystalline (μc) if deposited directly on stainless steel (SS) substrates but are fully amorphous provided a thin (20 nm) n-layer of a-Si:H or μc-Si:H is first deposited on the SS. The latter predeposition does not prevent partially microcrystallinity if the films are grown thicker (1.5 to 2.5 μm) and this is consistent with a recently proposed phase diagram of thickness versus hydrogen dilution. Analysis of the first (lowest angle) scattering peak of the a-Si:H phase demonstrates that its width, directly related to MRO, is reduced by heavier hydrogen dilution in PECVD growth or by increased substrate temperature in HWCVD growth. The narrowest width of fully amorphous material correlates with better solar cell stability and this is not likely related to bonded hydrogen content since it is quite different in the optimized PECVD and HWCVD a-Si:H. A wide range of MRO apparently exists in the residual amorphous phase of the mixed a/μc material.

A Theoretical Study of Condensation Processes in OMCVD of GaAs

1987 ◽  
Vol 94 ◽  
Author(s):  
S. K. Shastry
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Theoretical Study ◽  
Growth Models ◽  
Chemical Vapor ◽  
Growth Front ◽  
Hydrogen Chemisorption ◽  
The Past ◽  
Hydrogen Molecules ◽  
Kinetics Of

Kinetics of epitaxial growth of GaAs from trimethylgallium (TMG) and arsine in organometallic chemical vapor deposition (OMCVD) have been suggested in the past to occur according to the Langmuir-Hinshelwood (L-H) or Langmuir-Rideal (L-R) mechanism [1–3], where competitive chemisorption of the Ga- and As-containing species is assumed. In contrast, formation of sp3 bonds on the GaAs growth front suggests that the Ga-containing species are less likely to chemisorb onto Assites, while the As-containing species are less likely to chemisorb onto Ga-sites. In addition, an analysis of probable chemical reactions and the unlikely event of homogeneous dissociation of hydrogen molecules indicate that the chemisorption of hydrogen must be included in the growth kinetics. Since H-As and H-Ga bonds have similar characteristics, such hydrogen chemisorption probably occurs on all sites. Thus, a mix of selective (Ga, As) and competitive (H2) chemisorption processes is likely to be present in practice. Furthermore, the presence of chemisorbed hydrogen will alter the surface As bonds, which, in the absence of hydrogen, are known to dehybridize and dimerize[4]. These basic issues have not been addressed in existing OMCVD growth models. Therefore, an analysis of the adsorption and growth processes, in the epitaxy of (100)GaAs is presented in this paper, with particular attention to the above issues.

The formation mechanism of planar defects in compound semiconductors grown epitaxially on {100} silicon substrates

1989 ◽  
Vol 4 (4) ◽  
pp. 834-842 ◽  
Author(s):  
F. Ernst ◽  
P. Pirouz
Keyword(s):  
Chemical Vapor Deposition ◽  
Formation Mechanism ◽  
Vapor Deposition ◽  
Lattice Mismatch ◽  
Chemical Vapor ◽  
Compound Semiconductors ◽  
Organic Chemical ◽  
Minor Role ◽  
Silicon Substrates ◽  
Wide Range

Films of three compound semiconductors with the zincblende structure grown epitaxially on {100} silicon substrates by chemical vapor deposition or metal-organic chemical vapor deposition were investigated by transmission electron microscopy. The three systems have similar thermal mismatches but cover a wide range of lattice mismatch. From the comparison of the observed microstructures as well as from the investigation of early stages of film formation it is concluded that the lattice mismatch plays a minor role in the formation of stacking faults and twin boundaries. A formation mechanism is proposed for these defects which is based on deposition errors during the adsorption of atoms on {111} facets of film nuclei. The observed microstructural features are discussed in terms of this model.

Preparation of Silicon Carbide Nanowires and Nanochains Using Chemical Vapor Deposition Method

2016 ◽  
Vol 697 ◽  
pp. 841-845 ◽  
Author(s):  
Jia Xing Chang ◽  
Rong Zheng Liu ◽  
Ma Lin Liu ◽  
You Lin Shao ◽  
Bing Liu
Keyword(s):  
Silicon Carbide ◽  
Chemical Vapor Deposition ◽  
Electron Microscope ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Raw Material ◽  
Chemical Vapor Deposition Method ◽  
Deposition Method ◽  
X Ray ◽  
Wide Range

Silicon carbide nanowires have been extensively studied because of their unique physical and chemical properties. They can be applied in high temperature, high frequency, high power, and corrosive environments, and have a wide range of applications in electronics, chemical industry, energy and other fields. In this paper, SiC nanowires with high output were synthesized by chemical vapor deposition method using methyltrichlorosilane as raw material. The influences of the catalyst and temperature were studied. SiC nanochains were also obtained by adding Al2O3 powder under appropriate temperature controlled strategy. These two kinds of one-dimensional SiC nanomaterials were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectrometer (EDS) and transmission electron microscope (TEM) methods.

A mini review on chemical vapor deposition growth of wafer-scale h-BN single crystals

Nanoscale ◽  
2021 ◽  
Author(s):  
Lin Li ◽  
Ye Zhang ◽  
ruijie Zhang ◽  
Ziyi Han ◽  
Huanli Dong ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Boron Nitride ◽  
Single Crystals ◽  
Vapor Deposition ◽  
Flat Surface ◽  
Hexagonal Boron Nitride ◽  
Chemical Vapor ◽  
Chemical Vapor Deposition Growth ◽  
The Past ◽  
Excellent Stability

Hexagonal boron nitride (h-BN), with its excellent stability, flat surface and large bandgap, plays a role in a variety of fundamental science and technology fields. The past few years have...

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