Control of Crystal Orientation of Epitaxial Si nanowires on Si Substrate Using AAO template

2011 ◽  
Vol 1350 ◽  
Author(s):  
Tomohiro Shimizu ◽  
Qi Wang ◽  
Chonge Wang ◽  
Fumihiro Inoue ◽  
Makoto Koto ◽  
...  
Keyword(s):  
Crystal Orientation ◽  
Growth Direction ◽  
Nanowire Arrays ◽  
Si Nanowires ◽  
Aao Template ◽  
Si Substrate ◽  
Anodic Aluminum ◽  
Transmission Electron ◽  
Growth Method ◽  
Vls Growth

ABSTRACTControl of crystal orientation of vertically grown epitaxial Si (111) and (110) nanowire arrays on Si substrate has been demonstrated using a combination of an anodic aluminum oxide (AAO) template and vapor – liquid – solid (VLS) growth method. The crystal orientation of the nanowire was investigated by transmission electron microscopy. A growth direction of the nanowire arrays was guided perpendicular to the surface of the substrate by the AAO template, and the crystal orientation of the nanowire arrays was selected using the single crystal Si substrate properly cut in desired orientation.

Homoepitaxial Growth of Vertical Si Nanowires on Si(100) Substrate using Anodic Aluminum Oxide Template

2007 ◽  
Vol 1058 ◽  
Author(s):  
Tomohiro Shimizu ◽  
Tian Xie ◽  
Volker Schmidt ◽  
Jo Nishikawa ◽  
Shoso Shingubara ◽  
...  
Keyword(s):  
Aluminum Oxide ◽  
Epitaxial Growth ◽  
Anodic Aluminum Oxide ◽  
Growth Direction ◽  
Anodic Aluminum Oxide Template ◽  
Si Nanowires ◽  
Aao Template ◽  
Homoepitaxial Growth ◽  
Anodic Aluminum ◽  
Vls Growth

ABSTRACTHomo-epitaxial growth of Si nanowires on Si (100) substrate was accomplished using a combination of anodic aluminum oxide (AAO) template and Vapor-Liquid-Solid (VLS) growth. We prepared two types of AAO template for epitaxial growth of Si nanowires.We observed vertically grown epitaxial Si (100) nanowires in the AAO template. In addition, after leaving filled pores, Si nanowires changed their growth direction from [100] to <111>. This result shows that the walls of the pores forced the growth direction of Si nanowires parallel to the direction of the pores, and after complete filling, the growth direction changes to that of the Si nanowires on a bare Si substrate.

Morphological and Magnetic Properties of Electrodeposited Ni-Ag Alloy Nanowire Arrays in Modified AAO Template

2014 ◽  
Vol 875-877 ◽  
pp. 14-17 ◽  
Author(s):  
Wei Zheng Shang ◽  
Wei Guo Zhang ◽  
Hong Zhi Wang
Keyword(s):  
Electron Microscopy ◽  
Anodic Aluminum Oxide ◽  
Magnetic Hysteresis ◽  
Magnetic Hysteresis Loop ◽  
Atomic Ratio ◽  
Nanowire Arrays ◽  
Aao Template ◽  
Anodic Aluminum ◽  
Transmission Electron ◽  
Potential Applications

Highly ordered Ni-Ag alloy nanowire arrays have been fabricated successfully by electrodeposition into the pores of anodic aluminum oxide (AAO). This template was prepared with modified two-step anodizing method. The scanning and transmission electron microscopy were utilized to characterize the Ni-Ag alloy nanowire arrays. The results revealed that the nanowire arrays were regularly arranged, about 90nm in diameter and 30µm in length. The nanowires were single crystal and the atomic ratio of Ni and Ag is very close to 79:21. Magnetic hysteresis loop showed that Ni-Ag alloy nanowire arrays embedded in AAO have superparamagnetism, indicating their potential applications in biomedical materials.

Synthesis of Al-Catalyzed Si Nanowires Using the Al Remaining After Removal of Anodic Aluminum Oxide

2008 ◽  
Vol 8 (11) ◽  
pp. 6038-6042 ◽  
Author(s):  
Jin-Young Jung ◽  
Sang-Won Jee ◽  
Kwang-Tae Park ◽  
Jung-Ho Lee
Keyword(s):  
Aluminum Oxide ◽  
Silicon Nanowires ◽  
Atmospheric Pressure ◽  
Anodic Aluminum Oxide ◽  
Si Nanowires ◽  
Aao Template ◽  
Si Substrate ◽  
Anodic Aluminum ◽  
Resistance To Oxidation ◽  
Residual Al

Single-crystal, Al-catalyzed silicon nanowires were grown under atmospheric pressure using the dimpled feature of the Al metal that remained after removal of an anodic aluminum oxide (AAO) template directly formed on a Si substrate. Upon annealing in a hydrogen-rich atmosphere, the dimpled morphology of Al was transformed into a smooth, rounded shape in which Si nanodots were periodically embedded due to Si migration from the substrate. The positions of the nanodots were exactly the same as the positions of sawtooth features on the dimpled surface. Although Al-catalyzed silicon nanowires have been known to grow only under vacuum due to the tendency of Al to oxidize, these silicon nanodots, surrounded by residual Al, showed excellent resistance to oxidation under atmospheric pressure. These nanodots were also capable of acting as catalysts for the growth of nanowires, and played a role in determining the diameter of the nanowires. A thinner residual Al layer made it easier to form Si nanodots while reducing the size of the nanodots, which subsequently led to the growth of nanowires with smaller diameters and better crystalline morphology.

Controlled Growth of Carbon Spheres by Chemical Vapor Deposition Based on Anodic Aluminum Oxide Nano-Template

2012 ◽  
Vol 184-185 ◽  
pp. 924-927
Author(s):  
Lei Shan Chen ◽  
Cun Jing Wang ◽  
Gai Rong Chen
Keyword(s):  
Electron Microscopy ◽  
Vapor Deposition ◽  
Anodic Aluminum Oxide ◽  
Chemical Vapor ◽  
Average Diameter ◽  
Carbon Spheres ◽  
Aao Template ◽  
Graphene Layers ◽  
Anodic Aluminum ◽  
Transmission Electron

The reactions were carried out by decomposing acetylene at 1000 °C in a two-stage furnace system for 10 min. In the first furnace no catalyst was placed and an AAO template with the average diameter about 50 nm was placed in the second furnace whose temperature was designed to be 500 °C, 600 °C and 700 °C. The samples were characterized by scanning electron microscopy and high resolution transmission electron microscopy. The results show that carbon spheres with average diameter about 50 nm on the AAO template surface were obtained when the temperature of the second furnace was designed to be 700 °C. These carbon spheres are composed of unclosed graphene layers with an interlayer distance of 0.33–0.35 nm between the layers.

Synthesis of Straight Y-Shaped Silica Nanorods

2008 ◽  
Vol 47-50 ◽  
pp. 367-370
Author(s):  
Guang Zhu ◽  
Xiao Ping Zou ◽  
Jin Cheng ◽  
Mao Fa Wang ◽  
Yi Su
Keyword(s):  
Electron Microscopy ◽  
Smooth Surface ◽  
Growth Direction ◽  
Si Substrate ◽  
Transmission Electron ◽  
External Conditions ◽  
Uniform Diameter ◽  
Silica Nanorods ◽  
Scanning Electron ◽  
Si Wafer

The straight Y-shaped silica nanorods have been synthesized on Si wafer by thermal chemical evaporation of mixed powders of silica and graphite at 1300°C and condensation on Si substrate without assistance of any catalyst. The synthesized samples were characterized by means of scanning electron microscopy, transmission electron microscopy. The results suggested that the straight Y-shaped silica nanorods have uniform diameter about 50-200nm and neat smooth surface. The growth of such silica nanorods may be a result of the fluctuation of external conditions causing a change in the growth direction of silica nanorods developed.

SYNTHESIS AND LUMINESCENCE PROPERTIES OF ZnO:Eu3+ NANOWIRE ARRAYS VIA ELECTRODEPOSITED METHOD

2010 ◽  
Vol 03 (04) ◽  
pp. 285-288 ◽  
Author(s):  
SHIHUA ZHAO ◽  
LEI YANG ◽  
LINGLING WANG ◽  
BENHAI YU ◽  
YUXI CHEN ◽  
...  
Keyword(s):  
Dopant Concentration ◽  
Growth Direction ◽  
Nanowire Arrays ◽  
Sem Images ◽  
Alumina Membranes ◽  
Transmission Electron ◽  
Preferential Growth Direction ◽  
Zno Crystal ◽  
The Fourier Transform ◽  
Xrd Patterns

ZnO:Eu3+ nanowire arrays (NWAs) were prepared using anodic alumina membranes (AAMs) via an electrodeposited method. The XRD patterns, high resolution transmission electron microscopy (HRTEM) and infrared absorption spectra indicate that Eu3+ has entered ZnO crystal lattice. SEM images show that the as-prepared NWAs were embedded in Al2O3 nanotube arrays (NTAs) and the uniform diameters of those nanowires are about 80 nm. The Fourier Transform pattern of the HRTEM shows that the NWAs are single crystals with preferential growth direction along the [0001]. The PL spectra show that the ratio of relative emission intensity of 612 and 597 nm increases with the increase of dopant concentration of Eu3+ . There is no emission peak at 597 nm with the dopant concentration of 10% Eu3+ . The PL results also show that a new UV emission band centered at 306 nm appears.

Controllable Synthesis of Carbon Spheres Based on Anodic Aluminum Oxide Nano-Template

2011 ◽  
Vol 393-395 ◽  
pp. 32-35
Author(s):  
Cun Jing Wang ◽  
Peng Yao ◽  
Gai Rong Chen
Keyword(s):  
Electron Microscopy ◽  
Anodic Aluminum Oxide ◽  
Average Diameter ◽  
Carbon Spheres ◽  
Aao Template ◽  
Controllable Synthesis ◽  
Graphene Layers ◽  
Anodic Aluminum ◽  
Transmission Electron ◽  
Scanning Electron

The reactions were carried out by decomposing acetylene at 1000 °C in a two-stage furnace system for 10 min. In the first furnace no catalyst was placed and an AAO template with average diameter about 50 nm was placed in the second furnace whose temperature was designed to be 700 °C. The samples were characterized by scanning electron microscopy and high resolution transmission electron microscopy. The results show that carbon spheres with average diameter about 50 nm on the AAO template surface were obtained and these carbon spheres are composed of unclosed graphene layers with an interlayer distance of 0.33–0.35 nm between the layers.

Magnetic anisotropy and phohotoluminescence properties of amorphous CexFeyOn nanowire arrays

2021 ◽  
pp. 2151016
Author(s):  
Fangkuo Wang ◽  
Xiao-You Yuan
Keyword(s):  
Magnetic Anisotropy ◽  
Emission Intensity ◽  
Anodic Aluminum Oxide ◽  
Fluorescence Spectra ◽  
Nanowire Arrays ◽  
Aao Template ◽  
Anodic Aluminum ◽  
Regular Change ◽  
Axis Parallel ◽  
Co Precipitation

Amorphous Ce[Formula: see text]Fe[Formula: see text]O[Formula: see text] nanowire arrays with diameters about 100 nm were fabricated in porous anodic aluminum oxide (AAO) template channels by chemical co-precipitation assisted by suction filtration. Ce[Formula: see text]Fe[Formula: see text]O[Formula: see text] nanowire arrays have distinct magnetic anisotropy behavior, and the axis parallel to the nanowire is magnetically “easy.” The magnetic properties of Ce[Formula: see text]Mn[Formula: see text]O[Formula: see text] and Ce[Formula: see text]Fe[Formula: see text]Mn[Formula: see text]O[Formula: see text] nanowire arrays were investigated to compare with Ce[Formula: see text]Fe[Formula: see text]O[Formula: see text] nanowire arrays. The fluorescence spectra of Ce[Formula: see text]Fe[Formula: see text]O[Formula: see text] nanowires arrays mixed with Eu, Tb, Sm showed that their emission intensity displays regular change with the increase of the mole fraction of mixture. The emission intensity reached maximum with increasing of Eu or Sm-mixing from 2 mol% to 10 mol% at 591 nm, 709 nm or 607 nm, then decreased gradually. However, there is no obvious influence to fluorescence of Tb mixed Ce[Formula: see text]Fe[Formula: see text]O[Formula: see text] nanowire arrays, only one visible weak emission peak is present at 486 nm.

Synthesis and Characterization of Boron Carbide Nanobelts

2007 ◽  
Vol 336-338 ◽  
pp. 2166-2168 ◽  
Author(s):  
Xiao Qiang An ◽  
Hua Zhang Zhai ◽  
Chuan Bao Cao ◽  
He Sun Zhu
Keyword(s):  
Boron Carbide ◽  
Raw Materials ◽  
Growth Direction ◽  
Xrd Pattern ◽  
Molar Ratios ◽  
Growth Method ◽  
Vls Growth ◽  
Diffraction Peaks ◽  
Rhombohedral Boron

Boron carbide nanobelts have been synthesized successfully by carbothermal growth method. Boron oxide, activated carbon, gallium oxide and sodium chloride in the molar ratios of 1: 5: 0.03: 0.2 were used as raw materials. The width and thickness of the nanobelts range from 1 to 10 μm, and 80 to 150 nm respectively. The length is up to 50–200 μm. Diffraction peaks in the XRD pattern can be indexed to rhombohedral boron carbide with lattice parameters of a=5.616Å, c=12.067 Å. SAED pattern recorded along [ 010 ] zone axis shows (104 ) growth direction. A vapor–liquid–solid (VLS) growth process on the active catalyst surface is supposed to interpret the growth mechanism of as–synthesized nanobelts.

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