scholarly journals Thermal Strain Measurements in Epitaxial CoSi2/Si by Double Crystal X-Ray Diffraction

1988 ◽  
Vol 130 ◽  
Author(s):  
Gang Bai ◽  
Marc-A. Nicolet ◽  
Thad Vreeland ◽  
Q. Ye ◽  
Y. C. Kao ◽  
...  
Keyword(s):  
Growth Temperature ◽  
Room Temperature ◽  
Coefficient Of Thermal Expansion ◽  
Thermal Strain ◽  
Young Modulus ◽  
Film Stress ◽  
Misfit Dislocations ◽  
Double Crystal ◽  
Linear Coefficient ◽  
X Ray

AbstractThe perpendicular x-ray strain of epitaxial CoSi2 films grown on Si(111) substrates at ∼ 600°C by MBE was measured at various temperatures. Within experimental error margins, the strain decreases linearly with rising temperature at a rate of (1.3±0.1) × 10-5/°C from room temperature up to 600°C. Over that temperature range and the duration of a complete measurement (∼5h to ∼ 2h), these strain values remain reversible. At 593°C, the x-ray strain is -0.85%, which is about the strain that a stress-free CoSi2 film on Si(111) would have at that temperature. This results show that the stress in the epitaxial CoSi2 film is fully relaxed at the growth temperature. Strains below the growth temperature are induced in the film by the difference in the linear coefficient of thermal expansion of CoSi2 and Si. They were calculated by assuming that the density of misfit dislocations formed at the growth temperature remains constant. The slope of the strain-temperature dependence obtained that way agrees with the measured slope if the unknown Possion ratio of CoSi2 is assumed to be VcoSi2 = 0.35. A film stress of ∼ 0.8 GPa at room temperature was calculated using the above value for the Possion ratio, 130 GPa for the Young modulus, and the measured x-ray strain.

Thermal Strain Study of Almost Lattice-Matched Epitaxial InuGa1-uAs1-vP1-v Films on InP(100) Substrates

1989 ◽  
Vol 160 ◽  
Author(s):  
G. Bai ◽  
M-A. Nicolet ◽  
S.-J. Kim ◽  
R.G. Sobers ◽  
J.W. Lee ◽  
...  
Keyword(s):  
Room Temperature ◽  
Epitaxial Film ◽  
Lattice Mismatch ◽  
Thermal Strain ◽  
Growth Direction ◽  
Epitaxial Films ◽  
Double Crystal ◽  
X Ray ◽  
Lattice Matched ◽  
Coherent Interfaces

AbstractSingle layers of ~ 0.5µm thick InuGa1-uAs1-vPv (0.52 < u < 0.63 and 0.03 < v < 0.16) were grown epitaxially on InP(100) substrates by liquid phase epitaxy at ~ 630°C. The compositions of the films were chosen to yield a constant banndgap of ~ 0.8 eV (λ = 1.55 µm) at room temperature. The lattice mismatch at room temperature between the epitaxial film and the substrate varies from - 4 × 10-3 to + 4 × 10-3. The strain in the films was characterized in air by x-ray double crystal diffractometry with a controllable heating stage from 23°C to ~ 700°C. All the samples have an almost coherent interfaces from 23°C to about ~ 330°C with the lattice mismatch accomodated mainly by the tetragonal distortion of the epitaxial films. In this temperature range, the x-ray strain in the growth direction increases linearly with temperature at a rate of (2.0 ± 0.4) × 10-6/°C and the strain state of the films is reversible. Once the samples are heated above ~ 300°C, a significant irreversible deterioration of the epitaxial films sets in.

The Linear Coefficient of Thermal Expansion of Silicon at Room Temperature

1991 ◽  
Vol 6 (3) ◽  
pp. 147-152 ◽  
Author(s):  
Liu Fengchao ◽  
Zheng Bin
Keyword(s):  
Thermal Expansion ◽  
Single Crystal ◽  
Room Temperature ◽  
Coefficient Of Thermal Expansion ◽  
Silicon Single Crystal ◽  
Linear Coefficient ◽  
X Ray ◽  
Crystal State ◽  
Powder Diffractometer ◽  
Powder Samples

AbstractThe linear coefficient of thermal expansion for three silicon single-crystal samples, taken from the head, middle, and tail of the same boule, and their powder samples have been measured at room temperature by using an X-ray powder diffractometer. All samples yield the same expansion value α=2.45 (± 0.04) × 10−6 °C at 25 °C. The results of this experiment show that the linear coefficient of thermal expansion of silicon at room temperature is not dependent on its single-crystal state or its powder state.

Generation of Defects and Strain by Ion Implantation in Ge (100) Single Crystals, and in Pseudomorphic GexSi1-x Films Grown on Si (100)

1992 ◽  
Vol 262 ◽  
Author(s):  
D. Y. C. Lie ◽  
A. Vantomme ◽  
F. Eisen ◽  
M. -A. Nicolet ◽  
V. Arbet-Engels ◽  
...  
Keyword(s):  
Ion Implantation ◽  
Single Crystals ◽  
Room Temperature ◽  
Defect Concentration ◽  
Double Crystal ◽  
X Ray ◽  
Positive Strain ◽  
Independent Coefficient ◽  
The Relationship ◽  
Si Ion Implantation

ABSTRACTWe have studied the damage and strain produced in Ge (100) single crystals by implantation of various doses of 300 keV 28Si ions at room temperature. The analyzing tools were x-ray double-crystal diffractometry, and MeV 4He channeling spectrometry. The damage induced by implantation produces positive strain in Ge (100). The maximum perpendicular strain and maximum defect concentration rise nonlinearly with increasing dose. These quantities are linearly related with a dose-independent coefficient of ∼ 0.013 for Ge (100) single crystals implanted at room temperature. The results are compared with those available for Si (100) self-implantation. We have also monitored the strain and defects generated in pseudomorphic Ge0.1Si0.9/Si (100) films induced by room temperature 28Si ion implantation. It is found that the relationship between the strain and defect concentration induced by ion implantation is no longer a simple linear one.

scholarly journals Characteristics of MOCVD-Grown High-Quality CdTe Layers on GaAs Substrates

1995 ◽  
Vol 18 (4) ◽  
pp. 247-258
Author(s):  
P. W. Sze ◽  
K. F. Yarn ◽  
Y. H. Wang ◽  
M. P. Houng ◽  
G. L. Chen
Keyword(s):  
Growth Temperature ◽  
Vapor Deposition ◽  
Gaas Substrate ◽  
Concentration Ratio ◽  
Metalorganic Chemical Vapor Deposition ◽  
Chemical Vapor ◽  
Double Crystal ◽  
X Ray ◽  
Gaas Substrates ◽  
Growth System

CdTe epitaxial layers are grown successfully on a (100)-GaAs substrate by metalorganic chemical vapor deposition (MOCVD) using dimethylcadrnium (DMCd) and diethyltelluride (DETe) as alkyl sources. The CdTe epilayers grown between 365°C and 380°C possess the best surface morphology. DETe is used as the controlling species of this growth system. Typical growth rates are varied from 2.51µm/hr to 5.31µm/hr. Low-temperature (12K) photoluminscence (PL) measurements reveal that 380°C is the best growth temperature and the full width at half maximum (FWHM) of the dominated peak is about 1.583eV by the bound-exciton emission of 9.38meV. The double crystal X-ray rocking curves (DCRC) indicate that the FWHM decreases while increasing the epilayer thickness and approaches a stable value about 80 arc sec under the growth rate of 5.2µm/hr, the growth temperature of 380°C and the DETe/DMCd concentration ratio of 1.7. The value of 80 arc sec in FWHM is the smallest one ever reported to date.

MOCVD Growth and Characterization of High-Quality ZnSe on GaAs

1994 ◽  
Vol 340 ◽  
Author(s):  
J. C. Chen ◽  
Bing Yang ◽  
F. Semendy ◽  
W. W. Clark ◽  
P. R. Boyd ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Secondary Ion Mass Spectrometry ◽  
Defect Density ◽  
Growth Conditions ◽  
Misfit Dislocations ◽  
High Quality ◽  
Double Crystal ◽  
X Ray ◽  
Mocvd Growth ◽  
Order Of Magnitude

ABSTRACTHigh-quality ZnSe epilayers on GaAs substrates have been grown by MOCVD. Diethylzinc (DEZn) and diethylselenide (DESe) were used as source materials. Growth studies were done at 400°C under different growth conditions in an atmospheric pressure MOCVD reactor. The as-grown ZnSe epilayers were characterized by a wide variety of techniques, such as double crystal x-ray diffraction, low-temperature photoluminescence (PL), transmission electron microscopy (TEM), secondary ion mass spectrometry (SIMS), and scanning electron microscopy (SEM).The results show excellent structural and optical properties of ZnSe. The best material was grown on undoped GaAs at the VI/II ratio near unity. The full-width-at-half-maximum (FWHM) of ZnSe (∼0.2/μm thick) x-ray peak as low as 90 arc seconds was achieved. TEM results also show very low defect density. The density of stacking faults is less than 105/cm2 which is four orders of magnitude less than that of samples grown by conventional MBE [J. Petruzzello et al. J. Appl. Phys. 63, 2299 (1988)] and MOCVD [J.L. Batstone et al. Philos. Mag A, 66, 609, 1992]. The spacing between misfit dislocations is between 5 to 10,μm which is one order of magnitude larger than that of reported sample of comparable thickness.

scholarly journals Тепловое расширение кристаллов Pb-=SUB=-1-x-=/SUB=-Cd-=SUB=-x-=/SUB=-Te

2021 ◽  
Vol 55 (12) ◽  
pp. 1216
Author(s):  
М.К. Шаров
Keyword(s):  
Thermal Expansion ◽  
High Temperature ◽  
Solid Solutions ◽  
Coefficient Of Thermal Expansion ◽  
Cadmium Content ◽  
Lattice Period ◽  
Linear Coefficient ◽  
X Ray ◽  
Temperature Range

The values of the lattice period and the linear coefficient of thermal expansion (alfa) of Pb1-xCdxTe solid solutions are determined depending on the cadmium content and temperature using high-temperature X-ray diffractometry. Аn increase in the concentration of cadmium in Pb1-xCdxTe in the range x = 0.02–0.08 leads to a significant increase in the linear coefficient of thermal expansion. A change in temperature range T = 293–673 K leads to decrease in the linear coefficient of thermal expansion. Besides, an increase in temperature does not affect the value alfa of the undoped PbTe in the indicated temperature range.

Determination of heteroepitaxial layer relaxation at growth temperature from room temperature X-ray reciprocal space maps

2013 ◽  
Vol 368 ◽  
pp. 21-28 ◽  
Author(s):  
Tobias Roesener ◽  
Vera Klinger ◽  
Christoph Weuffen ◽  
David Lackner ◽  
Frank Dimroth
Keyword(s):  
Growth Temperature ◽  
Room Temperature ◽  
Reciprocal Space ◽  
X Ray

Study of Boron Implantation in CdTe

1988 ◽  
Vol 100 ◽  
Author(s):  
D. N. Jamieson ◽  
R. C. Bowman ◽  
P. M. Adams ◽  
J. F. Knudsen ◽  
R. G. Downing
Keyword(s):  
Room Temperature ◽  
Rutherford Backscattering Spectrometry ◽  
Depth Profiling ◽  
Liquid Nitrogen Temperature ◽  
Neutron Depth Profiling ◽  
X Ray Diffraction ◽  
Double Crystal ◽  
X Ray ◽  
Boron Implantation ◽  
Induced Structure

ABSTRACTThe effect of large dose boron implantation in single crystal CdTe has been investigated by Rutherford Backscattering Spectrometry with channeling (RBS), double crystal x-ray diffraction (DCD) and photoreflectance spectroscopy (PR). Comparisons are made with the results of identical B implantations of Si and GaAs crystals. Multiple energy implantations were performed at room temperature and liquid nitrogen temperature with total doses up to 1.5×1016 B+ ions/cm2. The implanted B distribution was measured with neutron depth profiling (NDP) and found to agree well with Monte-Carlo ion range calculations. The RBS results showed that the CdTe crystals had not been rendered completely amorphous even for the highest dose implantation, unlike GaAs and Si. Furthermore, the DCD results showed little implantation induced structure in the rocking curves from the implanted CdTe crystals, in contrast to GaAs. The consequences of annealing at 500°C in an attempt to regrow the crystal structure are also discussed.

Enhanced Hardness and Stress-Driven Delamination in Fe/Pt Multilayers

1995 ◽  
Vol 382 ◽  
Author(s):  
B.J. Daniels ◽  
W.D. Nix ◽  
B.M. Clemens
Keyword(s):  
Room Temperature ◽  
Multilayer Films ◽  
Film Structure ◽  
Film Stress ◽  
X Ray Diffraction ◽  
X Ray ◽  
Bilayer Period ◽  
Sputter Deposited ◽  
Epitaxial Multilayers ◽  
Qualitative Discussion

ABSTRACTPolycrystalline Fe/Pt multilayers of varying bilayer period, Λ, were sputter deposited onto SiO2 at room temperature. Film structure was characterized by x-ray diffraction, hardness was determined using nanoindentation, and stresses were examined with wafer curvature. The Fe layers were shown to be predominantly {110} oriented while the Pt layers were mostly {111} oriented. The hardnesses of these multilayer films were enhanced over the rule of mixtures value by a factor of almost 3 and exhibited a dependence on Λ which was similar to that previously observed in epitaxial Fe(001)/Pt(001) multilayers. The hardnesses of the polycrystalline multilayers were higher than those of the epitaxial multilayers, presumably due to grain boundary strengthening in these films. Film stress was large (∼1.5 GPa) and compressive, resulting in buckling-driven delamination of the film from the substrate for films with 40≤Λ≤100 Å. Delamination occurred in the “telephone cord” morphology and was observed in real time. A qualitative discussion of our observations of this delamination mechanism is presented.

Film Stress in Pd2Si Layers of Varying Thickness

1985 ◽  
Vol 47 ◽  
Author(s):  
Betty Coulman ◽  
Haydn Chen ◽  
Kenneth Ritz
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Film Stress ◽  
X Ray Diffraction ◽  
Double Crystal ◽  
X Ray ◽  
Si Substrates ◽  
Varying Thickness ◽  
Si Films ◽  
Low Coverage

ABSTRACTLittle is known about the development of film stresses in very thin films (thicknesses of the order of a few hundred Angstroms or less). As interest intensifies in the technological application of ever smaller quantities of materials, the behavior of very thin. films will undergo increasing scrutiny. In this study, the film stresses in evaporated Pd films and Pd2Si films formed by reaction with the Si substrates at 250°C were measured for thicknesses ranging from 7 to 107 nm. Stresses were calculated from the substrate radii of curvature determined by X-ray diffraction topography techniques (Lang and double crystal) and Stoney's equation. Because film continuity cannot be taken for granted at low coverage, the films were examined by electron microscopy in an attempt to correlate their morphology with the observed stresses.

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