On the Critical Layer Thickness of Strained-Layer Heteroepitaxial CoSi2 Films on 〈111〉Si

1987 ◽  
Vol 91 ◽  
Author(s):  
David N. Jamieson ◽  
G. Bai ◽  
Y. C. Kao ◽  
C. W. Nieh ◽  
M-A. Nicolet ◽  
...  
Keyword(s):  
Critical Thickness ◽  
Ion Beam ◽  
Thin Layers ◽  
Maximum Magnitude ◽  
Critical Layer Thickness ◽  
Double Crystal ◽  
Strained Layers ◽  
X Ray ◽  
Planar Growth

ABSTRACTThe technique of Double Crystal X-Ray Diffractometry (DXD) and ion beam channeling are applied to investigate, as a function of thickness, the average perpendicular strain and crystal quality of CoSi2 layers grown by MBE on 〈111〉Si. The results show that thin layers (from 20 to 30 nm) are partially relaxed but with a strain greater than that expected for a free CoSi2 lattice. For layers thicker than 30nm the magnitude of the CoSi2 strain incrgases to 1.7%, somewhat less than the maximum magnitude strain expected for coherent growth (2.1%). For layers thicker than 50 nm, the perpendicular strain relaxes very slowly, with the strain at 225 nm only 5% less than that at 50nm. It was concluded that a coherent epitaxial layer does not form initially and the relaxation of the strained layers is not consistent with a planar growth mechanism of the CoSi2 epilayers. Therefore the concept of a critical thickness, below which the epilayers are strained and above which the epilayers are relaxed, cannot be applied to our CoSi2/Si system.

Tetragonal Strain in MBE GexSi1-x Films Grown on (100) Si Observed by Ion Channeling and X-Ray Diffraction

1983 ◽  
Vol 25 ◽  
Author(s):  
A. T. Fiory ◽  
L. C. Feldman ◽  
J. C. Bean ◽  
I. K. Robinson
Keyword(s):  
Molecular Beam ◽  
Critical Thickness ◽  
Ion Beam ◽  
Growth Surface ◽  
X Ray Diffraction ◽  
Strained Layers ◽  
X Ray ◽  
Ion Channeling ◽  
Pseudomorphic Growth ◽  
Beam Damage

ABSTRACTStructure of GexSi1-x alloy films grown on (100) Si by molecular beam epitaxy is analyzed by MeV He+ ion channeling and X-ray diffraction as functions of Ge concentration, film thickness and growth temperature. Critical thicknesses for pseudomorphic growth are determined for x ≤ 0.5, where coherent tetragonally-strained layers are observed. The average strain decreases approximately as the square-root of thickness when the critical thickness is exceeded. At temperatures near the threshold for islanding growth, surface roughness appears as a precursor to degradation of strained-layer epitaxy. No effect on the amount of the tetragonal strain was found in a study of ion-beam damage.

Characterization of Natural and Synthesized FeTiO3 Crystals With RBS/PIXE/XRD

1997 ◽  
Vol 07 (03n04) ◽  
pp. 265-275
Author(s):  
R. Q. Zhang ◽  
S. Yamamoto ◽  
Z. N. Dai ◽  
K. Narumi ◽  
A. Miyashita ◽  
...  
Keyword(s):  
Single Crystals ◽  
Ion Beam ◽  
Pressure Control ◽  
Floating Zone ◽  
X Ray Diffraction ◽  
X Ray ◽  
Beam Analysis ◽  
Ppm Level

Natural FeTiO 3 (illuminate) and synthesized FeTiO 3, single crystals were characterized by Rutherford backscattering spectroscopy combined with channeling technique and particle-induced x-ray emission (RBS-C and PIXE). The results obtained by the ion beam analysis were supplemented by the x-ray diffraction analysis to identify the crystallographic phase. Oriented single crystals of synthesized FeTiO 3 were grown under the pressure control of CO 2 and H 2 mixture gas using a single-crystal floating zone technique. The crystal quality of synthesized FeTiO 3 single crystals could be improved by the thermal treatment but the exact pressure control is needed to avoid the precipitation of Fe 2 O 3 even during the annealing procedure. Natural FeTiO 3 contains several kinds of impurities such as Mn , Mg , Na and Si . The synthesized samples contain Al , Si and Na which are around 100 ppm level as impurities. The PBS-C results of the natural sample imply that Mn impurities occupy the Fe sublattice in FeTiO 3 or in mixed phase between ilmenite and hematite.

Growth of MBE-Codeposited IrSi3 on Si(111) and Si(100)

1994 ◽  
Vol 299 ◽  
Author(s):  
Gary A. Gibson ◽  
Davis A. Lange ◽  
Charles M. Falco
Keyword(s):  
Ion Beam ◽  
Silicide Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Low Energy Electron Diffraction ◽  
Growth Modes ◽  
Transmission Electron ◽  
Low Energy Electron

AbstractWe have used Molecular Beam Epitaxy (MBE) to successfully grow films that are predominantly IrSi3 on both Si(111) and Si(100) substrates by codeposition of Si and Ir in a 3:1 ratio. Bragg-Brentano and Seemann-Bohlin x-ray diffraction reveal that polycrystalline IrSi3 films form as low as 450 °C. This is the lowest temperature yet reported for growth of this iridium silicide phase. These x-ray diffraction techniques, along with Transmission Electron Microscope (TEM) diffraction and in situ Low Energy Electron Diffraction (LEED), show that at higher deposition temperatures codeposition can form IrSi3 films on Si(111) that consist predominantly of a single epitaxial growth orientation. Ion beam channeling and x-ray rocking curves show that the epitaxial quality of IrSi3 films deposited on Si(111) is superior to that of IrSi3 films deposited on Si(100). We also present evidence for several new epitaxial IrSi3 growth modes on Si(111) and Si(100).

Crystalline Structure and the Role of Low-Temperature-Deposited AlN and GaN on Sapphire Revealed by X-Ray CTR Scattering and X-Ray Reflectivity Measurements

2003 ◽  
Vol 10 (02n03) ◽  
pp. 537-541 ◽  
Author(s):  
Y. Takeda ◽  
M. Tabuchi ◽  
H. Amano ◽  
I. Akasaki
Keyword(s):  
Low Temperature ◽  
Crystalline Structure ◽  
Thin Layers ◽  
X Ray ◽  
Atomic Force ◽  
Crystal Truncation Rod ◽  
Before And After ◽  
Afm Observation

Crystalline and morphological quality of low-temperature (LT)-deposited and annealed AlN and GaN thin layers were investigated by X-ray crystal truncation rod (CTR) scattering and X-ray reflectivity measurements and atomic force microscope (AFM) observation. It was revealed that the LT-AlN layer was more uniform in terms of the crystalline structure and the layer thickness than the LT-GaN layer, before and after annealing. It suggests that LT-AlN is more suitable as a buffer layer between sapphire substrate and GaN.

CdTe Films Grown on InSb Substrates by Organometallic Epitaxy

1986 ◽  
Vol 90 ◽  
Author(s):  
I. B. Bhat ◽  
N. R. Taskar ◽  
J. Ayers ◽  
K. Patel ◽  
S. K. Ghandhi
Keyword(s):  
Secondary Ion Mass Spectrometry ◽  
Organometallic Vapor Phase Epitaxy ◽  
X Ray Diffraction ◽  
Double Crystal ◽  
Rocking Curve ◽  
X Ray ◽  
Cdte Films ◽  
Secondary Ion ◽  
Cdte Growth

ABSTRACTCadmium telluride layers were grown on InSb substrates by organometallic vapor phase epitaxy and examined using secondary ion mass spectrometry (SIMS), photoluminescence (Pb) and double crystal x-ray diffraction (DCD). The substrate temperature and the nature of the surface prior to growth are shown to be the most important parameters which influence the quality of CdTe layers. Growth on diethyltelluride (DETe) stabilized InSb substrates resulted in CdTe growth with a misorientation of about 4 minutes of arc with respect to the substrates. On the other hand, the grown layers followed the orientation of the substrates when a dimethylcadmium (DMCd) stabilized InSb was used. Growth at 350°C resulted in the smallest x-ray rocking curve (DCRC) full width at half maximum (FWHM) of about 20 arc seconds.

Investigation on quality of cubic GaN/GaAs(100) by double-crystal X-ray diffraction

1999 ◽  
Vol 42 (5) ◽  
pp. 517-522
Author(s):  
Dapeng Xu ◽  
Rutian Wang ◽  
Hui Yang ◽  
Lianxi Zheng ◽  
Jianbin Li ◽  
...  
Keyword(s):  
X Ray Diffraction ◽  
Double Crystal ◽  
X Ray ◽  
Cubic Gan

Nanostructuration of Cr/Si layers induced by ion beam mixing

2013 ◽  
Vol 1514 ◽  
pp. 61-68
Author(s):  
L. Luneville ◽  
L. Largeau ◽  
C. Deranlot ◽  
N. Moncoffre ◽  
Y. Serruys ◽  
...  
Keyword(s):  
Concentration Profile ◽  
Ion Beam ◽  
Error Function ◽  
Ion Beam Mixing ◽  
X Ray ◽  
Microelectronic Devices ◽  
Simple Error

ABSTRACTThis work clearly demonstrates that the X Ray Reflectometry technique (XRR), extensively used to assess the quality of microelectronic devices can be a useful tool to study the first stages of ion beam mixing. This technique allows measuring the evolution of the Si concentration profile in irradiated Cr/Si layers. From the analysis of the XRR profiles, it clearly appears that the Si profile cannot be described by a simple error function.

Effects of Surface Preparation on Epitaxial GaN on 6H-SIC Deposited Via Mocvd

1998 ◽  
Vol 537 ◽  
Author(s):  
Z. Y. Xie ◽  
C. H. Wei ◽  
L. Y. Li ◽  
J. H. Edgar ◽  
J. Chaudhuri ◽  
...  
Keyword(s):  
Surface Preparation ◽  
Chemical Vapor ◽  
Crystal Quality ◽  
Differential Interference Contrast Microscopy ◽  
Double Crystal ◽  
X Ray ◽  
Interference Contrast Microscopy ◽  
The Many ◽  
Substrate Surfaces

AbstractA comparison was made of 6H-SiC surfaces etched with H2, C2H4/H2, and HCl/H2, and the resulting crystal quality of epitaxial GaN films deposited on these substrates. To remove the many fine scratches and to smooth the rough surfaces typical of commercial SiC substrates, the Si-face 6H-SiC substrates were etched in H2, C2H4/H2, and HCl/H2 at 1450°C. GaN was subsequently deposited on these etched surfaces after first depositing a low temperature GaN buffer layer via metalorganic chemical vapor deposition (MOCVD). The surface morphologies after etching and after GaN deposition were characterized by atomic force microscopy and Normaski differential interference contrast microscopy, while the crystal quality of the GaN films was assessed by double crystal x-ray rocking curves and x-ray topography. 6H-SiC substrate surfaces were improved in terms of the removal of scratches and the reduction of surface roughness, and both surface morphology and crystal quality of the subsequently deposited GaN films were enhanced. However, the dislocation density was not decreased by the surface etching. The best GaN film was produced by etching the substrate in pure H2 for 40 minutes before growth. Recommendations for the optimum substrate treatment are made.

{224} Plane X-Ray Diffraction Study of GaAs on Si Wafers Using a Conventional Double Crystal Diffractometer

1987 ◽  
Vol 91 ◽  
Author(s):  
J.W. Lee ◽  
D.K. Bowen ◽  
J.P. Salerno
Keyword(s):  
Incident Angle ◽  
Wafer Surface ◽  
X Ray Diffraction ◽  
Double Crystal ◽  
Near Surface ◽  
Rocking Curve ◽  
X Ray ◽  
Gaas On Si ◽  
Plane Diffraction

ABSTRACTIn an effort to evaluate the near surface crystal quality of GaAs on Si wafers, {224} plane diffraction were investigated using a conventional double crystal x-ray diffractometer without any high intensity radiation source. The x-ray incident angle to wafer surface varied from 3.6 to 9.6 degrees for different {224} planes due to the substrate tilt angle of 3 degrees. The GaAs to Si rocking curve intensity ratio increased significantly as the incident angle decreased. For the diffraction with 3.6 degree incident angle, only the GaAs peak was detected from the 3.5 um thick GaAs on Si wafer and the GaAs peak became narrower. These indicates that this conventional x-ray diffraction technique is applicable for the near surface quality evaluation of GaAs on Si wafers.

MOCVD growth of ZnCdSe on InP (001) substrates

1996 ◽  
Vol 441 ◽  
Author(s):  
Hon-Kit Won ◽  
S. K. Hark
Keyword(s):  
Critical Thickness ◽  
High Growth ◽  
Epitaxial Films ◽  
X Ray Diffraction ◽  
Double Crystal ◽  
X Ray ◽  
Mocvd Growth ◽  
Complete Relaxation ◽  
Composition And Structure

AbstractA series of ZnCdSe epitaxial films containing various amounts of Cd were grown on InP (001) substrates using DEZn, DMCd and DESe in the temperature range of 350 to 450°C. The composition and structure of the films were studied by EDX and high resolution X-ray diffraction techniques. It was found that Cd rich films were obtained at low while Zn rich films at high growth temperatures. Double-crystal rocking curves of the films showed that the Cd rich films have substantially fewer defects than similar films grown on GaAs. This improvement in structure is attributed to the closer match of the lattice parameters of lnP and ZnCdSe. The independent determination of composition and structure allowed us to measure the degree of relaxation of the films. We found that even for films whose thickness far exceeds the critical thickness, complete relaxation is not achieved.

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