LASER-INDUCED SELECTIVE CRYSTALLIZATION OF A-SiGe FILM

2002 ◽  
Vol 16 (28n29) ◽  
pp. 4203-4206 ◽  
Author(s):  
XIYING MA ◽  
XUEKANG CHEN ◽  
GAN WU ◽  
JIANPING YANG ◽  
ZHANGXU LEI
Keyword(s):  
Room Temperature ◽  
Chemical Vapor ◽  
X Ray Diffraction ◽  
X Ray ◽  
Si Substrates ◽  
Nanometer Materials ◽  
Selective Crystallization ◽  
Treated Sample ◽  
Before And After ◽  
Two Peaks

Laser induced pattern crystallization technique with pulsed KrF excimer (248 nm) laser was used to irradiation amorphous SiGe films prepared by plasma-enhanced chemical vapor deposition (PECVD) on Si substrates. The surface of laser treated sample was investigated by scanning electron microscopy (SEM), it was found that the film irradiated by KrF excimer composed by well-shaped square periodicity embedded in the a-SiGe matrix, and in each square there are laser induced SiGe nanocrystals. The size of SiGe crystals was estimated to be about 10 nm. The samples were analyzed by X-ray diffraction, Raman spectroscopy and photoluminescence analysis before and after crystallization. The Raman spectrum shows strong Ge-Ge, Si-Ge, and Si-Si vibrations that agree with those of crystalline Si 1-x Ge x alloy. Strong PL with two peaks at 720 nm and 750 nm was observed at room temperature in the crystallized film, whereas the uncrystallized sample emits no peaks. These results indicate that nanometer SiGe alloy were formed and laser-induced technology is an efficient technique to produce nanometer materials.

Low-Temperature Deposition and Characterization of AlxIn1-xN Thin Films

1996 ◽  
Vol 449 ◽  
Author(s):  
Guohua Qiu ◽  
J. O. Olowolafe ◽  
Tao Peng ◽  
K. M. Unruh ◽  
C. P. Swann ◽  
...  
Keyword(s):  
Room Temperature ◽  
Chemical Vapor ◽  
Optical Measurements ◽  
Bandgap Energy ◽  
Nitride Semiconductors ◽  
X Ray Diffraction ◽  
X Ray ◽  
Si Substrates ◽  
Temperature Deposition

ABSTRACTThin III-V nitride semiconductors fidms are commonly prepared using metalorganic chemical vapor deposition (MOCVD) and molecular beam epitaxy (MBE). These methods often require high temperatures (800–1000°C) for the films to grow epitaxially. In the present work, we deposited AlxIn1-xN films on Si substrates by reactive magnetron sputttering method at low substrate temperature. The properties of the films have been studied by RBS, x-ray diffraction, and optical measurements. The AlxIn1-xN films deposited at room temperature were confirmed to be crystalline by x-ray diffraction. Band gap energies of our AlxIn1-xN alloys varies from 1.9 ev to 4.2 ev The bandgap energy vs. lattice constant curve was constructed and confirmed to bow downwards.

Hot-mesh Chemical Vapor Deposition for 3C-SiC Growth on Si and SiO2

2005 ◽  
Vol 862 ◽  
Author(s):  
Kanji Yasui ◽  
Jyunpei Eto ◽  
Yuzuru Narita ◽  
Masasuke Takata ◽  
Tadashi Akahane
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
X Ray Diffraction ◽  
Rocking Curve ◽  
Mesh Structure ◽  
X Ray ◽  
Si Substrates ◽  
Substrate Temperatures ◽  
Sic Films

AbstractThe crystal growth of SiC films on (100) Si and thermally oxidized Si (SiO2/Si) substrates by hot-mesh chemical vapor deposition (HMCVD) using monomethylsilane as a source gas was investigated. A mesh structure of hot tungsten (W) wire was used as a catalyzer. At substrate temperatures above 750°C and at a mesh temperature of 1600°C, 3C-SiC crystal was epitaxially grown on (100) Si substrates. From the X-ray rocking curve spectra of the (311) peak, SiC was also epitaxially grown in the substrate plane. On the basis of the X-ray diffraction (XRD) measurements, on the other hand, the growth of (100)-oriented 3C-SiC films on SiO2/Si substrates was determined to be achieved at substrate temperatures of 750-800°C, while polycrystalline SiC films, at substrate temperatures above 850°C. From the dependence of growth rate on substrate temperature and W-mesh temperature, the growth mechanism of SiC crystal by HMCVD was discussed.

X-Ray Diffraction Studies on the Titanium-Nickel System

1962 ◽  
Vol 6 ◽  
pp. 74-84
Author(s):  
John V. Gilfrich
Keyword(s):  
Heat Treatment ◽  
Room Temperature ◽  
Stoichiometric Composition ◽  
Physical Property ◽  
X Ray Diffraction ◽  
X Ray ◽  
Property Data ◽  
Before And After ◽  
Titanium Nickel ◽  
Physical Property Data

AbstractX-ray diffraction studies were made on the Ti–Ni system around the stoichiometric composition of the intermetallic compound TiNi to clarify some confusion which has existed about the phase diagram in this region, and to explain some anomalies in the physical properties of this material. Wrought and cast samples were examined at room temperature both before and after heat treatment and at temperatures both above and below ambient. The compound TiNi does exist at room temperature. The phase purity of the particular sample was found to be greatly affected by such factors as minor variations in composition, heat treatment, and method of sample preparation. Some confirming metallographlc and physical property data will also be presented.

Zinc Oxide Nano Walls Synthesized by Chemical Vapor Deposition

2014 ◽  
Vol 608 ◽  
pp. 127-131 ◽  
Author(s):  
Suttinart Noothongkaew ◽  
Supakorn Pukird ◽  
Worasak Sukkabot ◽  
Ki Seok An
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Room Temperature ◽  
Chemical Vapor ◽  
Green Emission ◽  
X Ray Diffraction ◽  
Ultraviolet Emission ◽  
Axis Orientation ◽  
X Ray ◽  
Zno Nanostructure

ZnO nanowalls were synthesized by chemical vapor deposition at temperature of 650 °C for 1 hour on the silicon substrate. The morphologies of samples were characterized by scanning electron microscopy (SEM). The result from X-ray diffraction (XRD) confirmed that the ZnO nanowalls were vertical c-axis orientation. A room temperature Photoluminescence peak at 378 nm is ultraviolet emission (UV) and the broad peak at wavelengths around 450-650 nm is corresponding to the green emission of ZnO nanostructure. This synthesis may be applicable for gas sensor or solar cells.

Reactive Sputtering Growth and Characterizations of InN Thin Films on Si Substrates

2012 ◽  
Vol 545 ◽  
pp. 290-293
Author(s):  
Maryam Amirhoseiny ◽  
Hassan Zainuriah ◽  
Ng Shashiong ◽  
Mohd Anas Ahmad
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Rf Magnetron Sputtering ◽  
Rf Power ◽  
X Ray Diffraction ◽  
Nitrogen Gas ◽  
X Ray ◽  
Force Microscopy ◽  
Si Substrates ◽  
Atomic Force

We have studied the effects of deposition conditions on the crystal structure of InN films deposited on Si substrate. InN thin films have been deposited on Si(100) substrates by reactive radio frequency (RF) magnetron sputtering method with pure In target at room temperature. The nitrogen gas pressure, applied RF power and the distance between target and substrate were 2×10-2 Torr, 60 W and 8 cm, respectively. The effects of the Ar–N2 sputtering gas mixture on the structural properties of the films were investigated by using scanning electron microscope, energy-dispersive X-ray spectroscopy, atomic force microscopy and X-ray diffraction techniques.

Al2O3 as a Transition Layer for GaN and InGaN Growth on ZnO by MOCVD

2009 ◽  
Vol 1201 ◽  
Author(s):  
Nola Li ◽  
Shen-Jie Wang ◽  
William E. Fenwick ◽  
Andrew Melton ◽  
Chung-Lung Huang ◽  
...  
Keyword(s):  
Room Temperature ◽  
Chemical Vapor ◽  
Shallow Donor ◽  
Near Band Edge ◽  
Band Edge Emission ◽  
X Ray Diffraction ◽  
Edge Emission ◽  
X Ray ◽  
20 Nm ◽  
Related Level

AbstractGaN and InGaN layers were grown on annealed 20 and 50nm Al2O3/ZnO substrates by metalorganic chemical vapor deposition (MOCVD). GaN was only observed by high resolution x-ray diffraction (HRXRD) on 20 nm Al2O3/ZnO substrates. Room temperature photoluminescence (RT-PL) showed the red shift of the GaN near band-edge emission, which might be from oxygen incorporation forming a shallow donor-related level in GaN. HRXRD measurements revealed that (0002) InGaN layers were also successfully grown on 20nm Al2O3/ZnO substrates. In addition, thick InGaN layers (∼200-300nm) were successfully grown on Al2O3/ZnO and bare ZnO substrates. These results are significant as previous studies showed decomposition of the layer at InGaN thicknesses of 100nm or less.

Structural, Magnetic, and Electrical Properties of BiFe1-xMnxO3 Thin Films

2009 ◽  
Vol 1199 ◽  
Author(s):  
Danilo G Barrionuevo ◽  
Surinder P Singh ◽  
Maharaj S. Tomar
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Magnetic Measurements ◽  
Sol Gel ◽  
Ion Concentration ◽  
Ferromagnetic Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Si Substrates ◽  
Sol Gel Process

AbstractWe synthesized BiFe1-xMnxO3 (BFMO) for various compositions by sol gel process and thin films were deposited by spin coating on platinum Pt/Ti/SiO2/Si substrates. X-ray diffraction shows all the diffraction planes corresponding to rhombohedrally distorted perovskite BiFeO3 structure. The absence of any impurity phase in the films suggests the incorporation Mn ion preferentially to Fe site in the structure for low concentration. Magnetic measurements reveal the formation of ferromagnetic phase at room temperature with increased Mn substitution. On the other hand, ferroelectric polarization decreases with increasing Mn ion concentration. Raman studies suggest the dopant induced structural distortion.

scholarly journals Ag-induced a New Raman Mode in ZnO Microrods

2019 ◽  
Vol 25 (3) ◽  
pp. 227-230
Author(s):  
Jing WANG ◽  
Lina WANG ◽  
Meina WANG ◽  
Dan ZHOU ◽  
Yan MEI ◽  
...  
Keyword(s):  
Chemical Vapor ◽  
Raman Mode ◽  
X Ray Diffraction ◽  
Characteristic Mode ◽  
Raman Analysis ◽  
X Ray ◽  
Ag Doping ◽  
Si Substrates ◽  
Hexagonal Shape ◽  
Vapor Deposition Technique

The chemical vapor deposition technique was used to prepare the Ag doped ZnO microrods, which were located on Si substrates at two different positions.  The scanning electron microscopy revealed that the samples have a clear hexagonal shape. X-ray diffraction provided information about the preferential orientation along the c-axis. The Raman analysis revealed that a new Raman mode appears at 492 cm-1 due to Ag doping. As this mode has not been reported early, it could be used as a characteristic mode of Ag doping in Raman spectrum. The red shift of the E2 (high) mode proves the existence of tensile stress in the samples. DOI: http://dx.doi.org/10.5755/j01.ms.25.3.19130

Heterogeneous Strain Relaxation in GaAs on Si (100)

1988 ◽  
Vol 116 ◽  
Author(s):  
A. Freundlich ◽  
G. Neu ◽  
A. Leycuras ◽  
R. Carles ◽  
C. Verie
Keyword(s):  
Residual Stress ◽  
Low Temperature ◽  
Room Temperature ◽  
Strain Relaxation ◽  
Photoluminescence Excitation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Si Substrates ◽  
Low Temperature Photoluminescence ◽  
Epilayer Surface

AbstractResidual stress in MOVPE grown GaAs on (100)Si substrates is investigated using Haman spectroscopy, X-ray diffraction, low temperature photoluminescence and photoluminescence excitation spectroscopy experiments. At room temperature, 2 µm-thick GaAs/Si is found to be under biaxial (100) tensile stress of X = 1.8 ± 0.3 kbar, near the epilayer surface. The stress magnitude decreases as the distance from interface decreases. PL and PLE studies on post-growth thermally annealed GaAs/Si reveal coexistence of unstrained and strained GaAs.

Influence of Ammonia on the Fabrication of Aligned Carbon Nanotubes Using Thermal CVD

2011 ◽  
Vol 467-469 ◽  
pp. 312-315
Author(s):  
Gang Li ◽  
Wen Ming Cheng
Keyword(s):  
Carbon Nanotubes ◽  
Chemical Vapor ◽  
X Ray Diffraction ◽  
Vertical Alignment ◽  
X Ray ◽  
Force Microscopy ◽  
Si Substrates ◽  
Atomic Force ◽  
Aligned Carbon Nanotubes ◽  
20 Nm

Ultra-thin (20 nm) nickel catalyst films were deposited by sputtering on SiO2/Si substrates. At the pretreatments, ammonia (NH3) was conducted for different time in a thermal chemical vapor deposition (CVD) system. Pretreated samples were characterized using atomic force microscopy (AFM). After the pretreatment, acetylene was introduced into the chamber for 10 min, samples were characterized using scanning electron micrograph (SEM) and X-ray diffraction (XRD). It was concluded that NH3 pretreatment was very crucial to control the surface morphology of catalytic metals and thus to achieve the vertical alignment of carbon nanotubes (CNTs). With higher density of the Ni particles, better alignment of the CNTs can be obtained due to steric hindrance effect between neighboring CNTs.

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