Crystallization Behavior of the Amorphous Si1-xGex Films Deposited on SiO2 by Molecular Beam Epitaxy(MBE)

1994 ◽  
Vol 345 ◽  
Author(s):  
Chang-Won Hwang ◽  
Myung-Kwan Ryu ◽  
Ki-Bum Kim ◽  
Seung-Chang Lee ◽  
Chang-Soo Kim
Keyword(s):  
Crystallization Behavior ◽  
Solid Phase ◽  
Grain Morphology ◽  
Alloy Film ◽  
Solid Phase Crystallization ◽  
Tem Analysis ◽  
Thermal Budget ◽  
X Ray ◽  
Transmission Electron ◽  
Amorphous Si

AbstractWe have investigated solid phase crystallization behavior of the MBE grown amorphous Si1-xGex (x=0 to 0.53) layers using x-ray diffractometry and transmission electron microscopy (TEM). It is found that the thermal budget of the solid phase crystallization of the film is significantly reduced as the Ge concentration in the film is increased. In addition, we find that the amorphous Si film crystallizes with a strong (111) texture while the Si1-xGex alloy film crystallizes with a (311) texture suggesting that the solid-phase crystallization mechanism is changed by the incorporation of Ge. TEM analysis of the crystallized film shows that the grain morphology of the pure Si is an elliptical or a dendrite shape with a high density of microtwins in the grains while that of the Si0.47 Ge0.53 alloy is more or less equiaxed shape with a much low density of crystalline defects in them.

Analysis of the Crystallization Kinetics and Microstructure of Polycrystalline Sige Films by Optical Techniques

1999 ◽  
Vol 588 ◽  
Author(s):  
J. Olivares ◽  
P. Martín ◽  
A. Rodríguez ◽  
J. Sangrador ◽  
O. Martínez ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Crystallization Kinetics ◽  
Solid Phase ◽  
Grain Morphology ◽  
Optical Techniques ◽  
X Ray ◽  
Transmission Electron ◽  
Uv Reflectance ◽  
The One ◽  
Means Of Transmission

AbstractIn this work, two optical techniques, Raman spectroscopy and ultraviolet reflectance, have been used to characterize the solid phase crystallization kinetics and the microstructure of SiGe films deposited by LPCVD on oxidized Si wafers. The results have been compared to those obtained by X-ray diffractometry. The Ge fraction of the films (x) was in the 0−0.38 interval. The samples were crystallized at temperatures ranging from 525 to 600 °C. The crystallization kinetics follows Avrami's model. Two different behaviours have been observed depending on the Ge fraction of the films and the crystallization temperature: a) Either the three experimental techniques yield similar results, or b) the crystallization process, as monitored by UV reflectance and Raman spectroscopy, exhibits a greater incubation time than the one obtained if X-ray diffractometry is used. The results are discussed in terms of the identification of the nucleation sites, taking into account the probe depth of the different techniques and the preferred orientations of the grains. These techniques have also been used to characterize the presence of defects, the overall crystallinity and the surface roughness of the fully crystallized films. The results are correlated to the grain morphology and grain size, obtained by means of transmission electron microscopy.

Reducing the Thermal Budget of Solid Phase Crystallization of Amorphous Si Film Using $\bf Si_{0.47}Ge_{0.53}$ Seed Layer

1995 ◽  
Vol 34 (Part 2, No. 8B) ◽  
pp. L1031-L1033 ◽  
Author(s):  
Myung-Kwan Ryu ◽  
Jin-Won Kim ◽  
Tae-Hoon Kim ◽  
Ki-Bum Kim ◽  
Chang-Won Hwang
Keyword(s):  
Seed Layer ◽  
Solid Phase ◽  
Solid Phase Crystallization ◽  
Thermal Budget ◽  
Amorphous Si

Growth of Epitaxial IrSi3 Layers on Si(111)

1989 ◽  
Vol 160 ◽  
Author(s):  
T. L. Lin ◽  
C. W. Nieh
Keyword(s):  
Surface Morphology ◽  
Molecular Beam ◽  
Solid Phase ◽  
Single Mode ◽  
Growth Conditions ◽  
Tem Analysis ◽  
Mbe Growth ◽  
Good Surface ◽  
Transmission Electron

AbstractEpitaxial IrSi3 films have been grown on Si (111) by molecular beam epitaxy (MBE) at temperatures ranging from 630 to 800 °C and by solid phase epitaxy (SPE) at 500 °C. Good surface morphology was observed for IrSi3 layers grown by MBE at temperatures below 680 °C, and an increasing tendency to form islands is noted in samples grown at higher temperatures. Transmission electron microscopy (TEM) analysis reveals that the IrSi3 layers grow epitaxially on Si(111) with three epitaxial modes depending on the growth conditions. For IrSi3 layers grown by MBE at 630 °C, two epitaxial modes were observed with ~ 50% area coverage for each mode. Single mode epitaxial growth was achieved at a higher MBE growth temperature, but with island formation in the IrSi3 layer. A template technique was used with MBE to improve the IrSi3 surface morphology at higher growth temperatures. Furthermore, single-crystal IrSi3 was grown on Si(111) at 500 °C by SPE, with annealing performed in-situ in a TEM chamber.

Solute Segregation and Dynamics of Solid-Phase Crystallization In in and Sb-Implanted Silicon

1981 ◽  
Vol 4 ◽  
Author(s):  
J. Narayan ◽  
G. L. Olson ◽  
O. W. Holland
Keyword(s):  
Laser Power ◽  
Solid Phase ◽  
Solute Segregation ◽  
Dislocation Loops ◽  
Solid Phase Crystallization ◽  
Time Resolved ◽  
Plan View ◽  
Ion Channeling ◽  
Retrograde Solubility ◽  
Transmission Electron

ABSTRACTTime-resolved-reflectivity measurements have been combined with transmission electron microscopy (cross-section and plan-view), Rutherford backscattering and ion channeling techniques to study the details of laser induced solid phase epitaxial growth in In+ and Sb+ implanted silicon in the temperature range from 725 to 1500 °K. The details of microstructures including the formation of polycrystals, precipitates, and dislocations have been correlated with the dynamics of crystallization. There were limits to the dopant concentrations which could be incorporated into substitutional lattice sites; these concentrations exceeded retrograde solubility limits by factors up to 70 in the case of the Si-In system. The coarsening of dislocation loops and the formation of a/2<110>, 90° dislocations in the underlying dislocation-loop bands are described as a function of laser power.

scholarly journals Characterization of glycidyl methacrylate based magnetic nanocomposites

2019 ◽  
Vol 73 (1) ◽  
pp. 25-35
Author(s):  
Bojana Markovic ◽  
Vojislav Spasojevic ◽  
Aleksandra Dapcevic ◽  
Zorica Vukovic ◽  
Vladimir Pavlovic ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Magnetic Nanoparticles ◽  
Glycidyl Methacrylate ◽  
Mercury Porosimetry ◽  
Magnetic Nanocomposite ◽  
Magnetic Nanocomposites ◽  
Tem Analysis ◽  
X Ray ◽  
Force Microscopy ◽  
Transmission Electron

Magnetic and non-magnetic macroporous crosslinked copolymers of glycidyl methacrylate and trimethylolpropane trimethacrylate were prepared by suspension copolymerization and functionalized with diethylenetriamine. The samples were characterized by mercury porosimetry, scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS), Fourier transform infrared spectroscopy analysis (FTIR-ATR), thermogravimetric analysis (TGA), X-ray diffractometry (XRD), atomic force microscopy (AFM), transmission electron microscopy (TEM) and SQUID magnetometry. The FTIR-ATR analysis of synthesized magnetic nanocomposites confirmed the presence of magnetite and successful amino- functionalization. Non-functionalized and amino-functionalized nanocomposites exhibited superparamagnetic behavior at 300 K, with a saturation magnetization of 5.0 emu/g and 2.9 emu/g, respectively. TEM analysis of the magnetic nanocomposite has shown that magnetic nanoparticles were homogeneously dispersed in the polymer matrix. It was demonstrated that incorporation of magnetic nanoparticles enhanced the thermal stability of the magnetic nanocomposite in comparison to the initial non-magnetic macroporous copolymer.

Uniform Poly-Si TFTs for AMOLEDs Using Field-Enhanced Rapid Thermal Annealing

2007 ◽  
Vol 124-126 ◽  
pp. 447-450 ◽  
Author(s):  
Hyoung June Kim
Keyword(s):  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Thin Film Transistors ◽  
Solid Phase ◽  
Radiative Heating ◽  
Solid Phase Crystallization ◽  
Glass Substrates ◽  
Grain Structures ◽  
Amorphous Si ◽  
Si Thin Film

Polycrystalline Si thin film transistors (TFTs) have been fabricated through solid phase crystallization using field-enhanced rapid thermal annealing (FE-RTA) system. The system consists of inline furnace modules for preheating and cooling of the glass substrates and a process module for rapid radiative heating combined with alternating magnetic field induction. The FE-RTA system enables crystallization of amorphous Si at high throughputs without any glass damages. While the typical grain structures of poly-Si by FE-RTA are similar to those of solid phase crystallization, the residual amorphous Si and intragranular defects are reduced.

scholarly journals Surface Study of CuO Nanopetals by Advanced Nanocharacterization Techniques with Enhanced Optical and Catalytic Properties

Nanomaterials ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 1298 ◽  
Author(s):  
Muhammad Arif Khan ◽  
Nafarizal Nayan ◽  
Shadiullah Shadiullah ◽  
Mohd Khairul Ahmad ◽  
Chin Fhong Soon
Keyword(s):  
Photoelectron Spectroscopy ◽  
Catalytic Properties ◽  
Average Length ◽  
Tem Analysis ◽  
X Ray ◽  
Surface Study ◽  
Transmission Electron ◽  
One Step ◽  
Controlled Morphology ◽  
Xrd Patterns

In the present work, a facile one-step hydrothermal synthesis of well-defined stabilized CuO nanopetals and its surface study by advanced nanocharacterization techniques for enhanced optical and catalytic properties has been investigated. Characterization by Transmission electron microscopy (TEM) analysis confirmed existence of high crystalline CuO nanopetals with average length and diameter of 1611.96 nm and 650.50 nm, respectively. The nanopetals are monodispersed with a large surface area, controlled morphology, and demonstrate the nanocrystalline nature with a monoclinic structure. The phase purity of the as-synthesized sample was confirmed by Raman spectroscopy and X-ray diffraction (XRD) patterns. A significantly wide absorption up to 800 nm and increased band gap were observed in CuO nanopetals. The valance band (VB) and conduction band (CB) positions at CuO surface are measured to be of +0.7 and −1.03 eV, respectively, using X-ray photoelectron spectroscopy (XPS), which would be very promising for efficient catalytic properties. Furthermore, the obtained CuO nanopetals in the presence of hydrogen peroxide ( H 2 O 2 ) achieved excellent catalytic activities for degradation of methylene blue (MB) under dark, with degradation rate > 99% after 90 min, which is significantly higher than reported in the literature. The enhanced catalytic activity was referred to the controlled morphology of monodispersed CuO nanopetals, co-operative role of H 2 O 2 and energy band structure. This work contributes to a new approach for extensive application opportunities in environmental improvement.

Analysis of the Intermetallic Compound Formed in Hot Dip Aluminized Steel

2006 ◽  
Vol 15-17 ◽  
pp. 159-163 ◽  
Author(s):  
Kee Hyun Kim ◽  
Benny van Daele ◽  
Gustaaf Van Tendeloo ◽  
Yong Sug Chung ◽  
Jong Kyu Yoon
Keyword(s):  
Intermetallic Compound ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Liquid Aluminium ◽  
Thin Specimen ◽  
Tem Analysis ◽  
X Ray ◽  
Cell Parameters ◽  
Transmission Electron ◽  
Aluminized Steel

A hot dip aluminising process was carried out with a 1mm steel sheet dipped into the Al-10at.% Si melt in an automatic hot-dip simulator. When steel and liquid aluminium are in contact with each other, a thin intermetallic compound (IMC) is formed between the steel and the aluminium. The analysis and identification of the formation mechanism of the IMC is needed to manufacture the application products. Energy dispersive X-ray spectroscopy (EDX) and electron probe microanalysis (EPMA) are normally used to identify the phases of IMC. In the Al-Fe-Si system, numerous compounds with only slight differences in composition are formed. Consequently, EDX and EPMA are insufficient to confirm exactly the thin IMC with multiphases. In this study, transmission electron microscopy (TEM) analysis combined with EDX was used. The TEM sample was prepared with focused ion beam (FIB) sampling. The FIB lift-out technology is used to slice a very thin specimen with minimum contamination for TEM analysis. It is clearly shown that the IMC consists of Al-27 at. % Fe-10 at. % Si and is identified as Al8Fe2Si with a hexagonal unit cell (space group P63/mmc). The cell parameters are a= 1.2404nm and c= 2.6234nm.

Ge-rich Si1-XGeX Nanocrystal Formation by the Oxidation of As-Deposited Thin Amorphous Si0.7Ge0.3 Layer

2002 ◽  
Vol 727 ◽  
Author(s):  
Tae-Sik Yoon ◽  
Ki-Bum Kim
Keyword(s):  
Selective Oxidation ◽  
Oxidation Rate ◽  
Solid Phase ◽  
Amorphous Film ◽  
Alloy Film ◽  
Spatial Density ◽  
Solid Phase Crystallization ◽  
Higher Temperature ◽  
20 Nm ◽  
Kinetics Of

AbstractGe-rich Si1-XGeX nanocrystals are formed by the selective oxidation of Si during the dry oxidation of an amorphous Si0.7Ge0.3 layer. The oxidation kinetics of the alloy film shows the activation energies of linear and parabolic rate constants are about 1.35 and 1.02 eV, respectively, based on the model proposed by Deal and Grove. In addition, as a result of the selective oxidation of Si and Ge pile-up during the oxidation process, Ge-rich Si1-XGeX nanocrystals are formed with the size of 5.6 ± 1.7 nm and the spatial density of 3.6×1011/cm2 at 600°C. At higher temperature of 700 and 800°C, the size of nanocrystal is increased to about 20 nm. The nanocrystals formation by oxidation is thought to be due to higher oxidation rate at grain boundary than at bulk grain. Therefore, the dependence of size on temperature is explained with the grain size determined by solid phase crystallization of amorphous film, oxidation rate, and grain growth.

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