Extraction of Elastic Parameters of Heavily Boron-Doped Silicon Layer by Elimination of Misfit Dislocations

1995 ◽  
Vol 378 ◽  
Author(s):  
HO-JUN Lee ◽  
Chul-Hi Han ◽  
Choong-Ki Kim
Keyword(s):  
Young’S Modulus ◽  
Boron Concentration ◽  
Young's Modulus ◽  
Silicon Layer ◽  
Misfit Dislocations ◽  
Residual Tensile Stress ◽  
X Ray Diffraction ◽  
Elastic Parameters ◽  
Boron Doped ◽  
Doped Silicon

AbstractIn this paper, various elastic parameters of heavily boron-doped silicon layer have been extracted by eliminating the misfit dislocations in the layer. The dislocation-free silicon membranes doped with the boron concentration of 1.3 × 1020 atoms/cm3 have been fabricated and the Young’s modulus of 1.45 × 1012 dyn/cm2 and residual tensile stress of 2.7 × 109 dyn/cm2 have been extracted by blister method. From the Young’s modulus and residual stress, the residual tensile strain of 1.34 × 10−3, lattice constant of 5.424 Å, and misfit coefficient of 1.03 × 10−23 cm3/atom have been calculated. These parameters are very similar to those obtained from X-ray diffraction analysis and theory.

Mechanical properties of FeAlSi powders prepared by mechanical alloying from different initial feedstock materials

2019 ◽  
Vol 107 (2) ◽  
pp. 207 ◽  
Author(s):  
Jaroslav Čech ◽  
Petr Haušild ◽  
Miroslav Karlík ◽  
Veronika Kadlecová ◽  
Jiří Čapek ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Mechanical Alloying ◽  
Young’S Modulus ◽  
Milling Time ◽  
Young's Modulus ◽  
Element Model ◽  
X Ray Diffraction ◽  
X Ray ◽  
Powder Particles ◽  
Complete Homogenization

FeAl20Si20 (wt.%) powders prepared by mechanical alloying from different initial feedstock materials (Fe, Al, Si, FeAl27) were investigated in this study. Scanning electron microscopy, X-ray diffraction and nanoindentation techniques were used to analyze microstructure, phase composition and mechanical properties (hardness and Young’s modulus). Finite element model was developed to account for the decrease in measured values of mechanical properties of powder particles with increasing penetration depth caused by surrounding soft resin used for embedding powder particles. Progressive homogenization of the powders’ microstructure and an increase of hardness and Young’s modulus with milling time were observed and the time for complete homogenization was estimated.

scholarly journals X-ray Diffraction Analysis and Williamson-Hall Method in USDM Model for Estimating More Accurate Values of Stress-Strain of Unit Cell and Super Cells (2 × 2 × 2) of Hydroxyapatite, Confirmed by Ultrasonic Pulse-Echo Test

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2949
Author(s):  
Marzieh Rabiei ◽  
Arvydas Palevicius ◽  
Amir Dashti ◽  
Sohrab Nasiri ◽  
Ahmad Monshi ◽  
...  
Keyword(s):  
Young’S Modulus ◽  
Young's Modulus ◽  
Ultrasonic Pulse ◽  
High Accuracy ◽  
Unit Cell ◽  
Deformation Model ◽  
X Ray Diffraction ◽  
Uniform Deformation ◽  
X Ray ◽  
Pulse Echo

Taking into account X-ray diffraction, one of the well-known methods for calculating the stress-strain of crystals is Williamson-Hall (W–H). The W-H method has three models, namely (1) Uniform deformation model (UDM); (2) Uniform stress deformation model (USDM); and (3) Uniform deformation energy density model (UDEDM). The USDM and UDEDM models are directly related to the modulus of elasticity (E). Young’s modulus is a key parameter in engineering design and materials development. Young’s modulus is considered in USDM and UDEDM models, but in all previous studies, researchers used the average values of Young’s modulus or they calculated Young’s modulus only for a sharp peak of an XRD pattern or they extracted Young’s modulus from the literature. Therefore, these values are not representative of all peaks derived from X-ray diffraction; as a result, these values are not estimated with high accuracy. Nevertheless, in the current study, the W-H method is used considering the all diffracted planes of the unit cell and super cells (2 × 2 × 2) of Hydroxyapatite (HA), and a new method with the high accuracy of the W-H method in the USDM model is presented to calculate stress (σ) and strain (ε). The accounting for the planar density of atoms is the novelty of this work. Furthermore, the ultrasonic pulse-echo test is performed for the validation of the novelty assumptions.

Development of Young's modulus of natural illitic clay during the heating and cooling stages of firing

Clay Minerals ◽  
2019 ◽  
Vol 54 (3) ◽  
pp. 229-233 ◽  
Author(s):  
Tomáš Húlan ◽  
Igor Štubňa ◽  
Andrei Shishkin ◽  
Jurijs Ozolins ◽  
Štefan Csáki ◽  
...  
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Bound Water ◽  
Thermomechanical Analysis ◽  
X Ray Diffraction ◽  
Heating And Cooling ◽  
Thermal Expansion Coefficients

AbstractIllitic clay from the locality of Liepa, Latvia, was investigated using dynamic thermomechanical analysis during the heating and cooling stages of firing. Differential thermal analysis, thermogravimetry, thermodilatometry, X-ray diffraction and porosimetry were also performed to shed light on the processes influencing the elastic properties of clay. The increase in the Young's modulus (YM) at low temperatures was linked to the release of physically bound water. Above 850°C, the bulk density and YM both increased as a consequence of sintering. The YM was more sensitive to the progress of sintering compared to dimension changes. The YM values continued to increase during cooling until the glass-transition temperature was reached. At this temperature, the first microcracks caused by the differences in thermal expansion coefficients of the present phases were expected to appear. The YM showed a sharp V-shaped minimum at the β → α transition of quartz, which was a result of alternation of the mechanical radial stresses around the quartz grains. When the transition of quartz was completed, the YM continued to decrease because microcracks were still being created at the boundaries between the different phases. The decrease of the YM during cooling from the glass-transition temperature down to room temperature was ~50% for all of the firing temperatures and isothermal periods applied.

Mechanical Properties of Boron Doped Si and Si/SiO 2 Membranes

2002 ◽  
Vol 729 ◽  
Author(s):  
Gabe Kuhn ◽  
Todd Myers ◽  
Susmita Bose ◽  
Amit Bandyopadhyay
Keyword(s):  
Tensile Stress ◽  
Boron Concentration ◽  
Boron Doping ◽  
Residual Tensile Stress ◽  
Flexural Mode ◽  
Si Substrates ◽  
Boron Doped ◽  
Pzt Film ◽  
Processing Variables ◽  
Etch Stop

AbstractIn our research, PZT film actuated micro-machined Si substrates are being developed for numerous applications in which membranes are actuated primarily in flexural mode. Silicon wafers, 3-inches in diameter, underwent boron doping in order to act as an etch stop. Approximately 200-nm of SiO2 was grown on the boron-doped side of the wafers. Photolithography and backside etching using EDP resulted in 2-μm thick membranes. Using reactive ion etching (RIE), beam structures resulted from the membranes. Nano-mechanical testing of the beams indicated that there were substantial residual tensile stresses in these structures. Initial calculations reveal a tensile stress of 57.7 MPa in the Si/SiO2 beams. The residual tensile stress subsequently caused the overall beam stiffness to be two orders of magnitude higher than it would be without stress. After stripping the oxide with a buffered oxide etchant (BOE), a residual stress of 26.5 MPa was measured, which is presumably caused from the remaining boron concentration. The aim of this paper is to understand influences of boron doping and processing variables on residual stresses.

Elastic Properties and Structural Evolution of AgNi Superlattices

1991 ◽  
Vol 229 ◽  
Author(s):  
B. Rodmacq ◽  
V. Pelosin ◽  
J. Hillairet
Keyword(s):  
Young’S Modulus ◽  
Elastic Properties ◽  
Young's Modulus ◽  
Functional Dependence ◽  
Structural Evolution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Tension Tests ◽  
Prepared State ◽  
Dimensional Variation

AbstractSilver-nickel multilayers were prepared by sputtering at 100 K. X-ray diffraction, electrical resistivity and dimensional variation measurements were performed to structurally characterize these stratified materials, both in the as-prepared state and during the course of annealing cycles. Clearly, polycrystalline superlattices with marked (111) texture perpendicular to the strata are formed. We studied the elastic properties of these superlattices by performing uniaxial tension tests. No deviation from linear elasticity was observed, whatever the period. Young's modulus was found to be 130±15 GPa for all the periods studied. Thus no significant functional dependence of Young's modulus on the stacking periodicity exists in the AgNi superlattice, in the range of periods explored, 2.6 to 18 nm.

Role of pH on stability and mechanical properties of gelatin films

2012 ◽  
Vol 27 (1) ◽  
pp. 67-77 ◽  
Author(s):  
Michela Gioffrè ◽  
Paola Torricelli ◽  
Silvia Panzavolta ◽  
Katia Rubini ◽  
Adriana Bigi
Keyword(s):  
Mechanical Properties ◽  
Young’S Modulus ◽  
Triple Helix ◽  
Young's Modulus ◽  
In Vitro Tests ◽  
Diffraction Reflection ◽  
X Ray Diffraction ◽  
Solution Ph ◽  
Gelatin Films

The effect of the film-forming solution pH on the triple-helix content, thermal stability, and mechanical properties of gelatin films was investigated. The films were prepared from solutions at different pHs of type A pigskin gelatin, and their mechanical characteristics were determined. At pHs higher than 9 and lower than 5, Young’s modulus, E, and the stress at break, σb, of the films decreased significantly. Cross-linking with genipin reduced deformation at break, ϵb, and increased Young’s modulus. The intensity of the 1.1-nm X-ray diffraction reflection and the denaturation enthalpy decreased at these pHs, indicating that the triple helix reduced. Preliminary in vitro tests on the cross-linked samples indicated good cell proliferation and viability.

Misfit Dislocations in Bicrystals of Epitaxially Grown Silicon on Boron‐Doped Silicon Substrates

1969 ◽  
Vol 40 (8) ◽  
pp. 3089-3094 ◽  
Author(s):  
Yoshimitsu Sugita ◽  
Masao Tamura ◽  
Katsuro Sugawara
Keyword(s):  
Silicon Substrates ◽  
Misfit Dislocations ◽  
Boron Doped ◽  
Doped Silicon

Room-Temperature Mechanical Characterization of Bulk Glassy and Partially Crystallized Zr63Al9.7Ni9.7Cu14.6Nb3 Alloys

2009 ◽  
Vol 633-634 ◽  
pp. 675-683
Author(s):  
F.W. Li ◽  
Jian Bing Qiang ◽  
S.G. Quan ◽  
Qing Wang ◽  
Chuang Dong ◽  
...  
Keyword(s):  
Young’S Modulus ◽  
Room Temperature ◽  
Young's Modulus ◽  
Cast Alloy ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Transmission Electron ◽  
Plastic Deformation Process ◽  
Icosahedral Quasicrystals ◽  
Constant Heating

The microstructures and mechanical behavior of the as-cast and isothermally annealed Zr63Al9.7Ni9.7Cu14.6Nb3 bulk metallic glasses (BMGs) were studied by differential scanning calorimetry (DSC), X-ray diffraction (XRD), transmission electron microscopy (TEM), and room temperature uniaxial compression. The as-cast BMG alloy shows a wide undercooled liquid span of 73 K at a constant heating rate of 40 K/min. Composite microstructures containing nanometer scaled icosahedral quasicrystals (i-phase) were produced upon annealing at 705 K. Under uniaxial room-temperature compression at a strain rate of 510-4 s-1, the as-cast BMG alloy exhibits a elastic deformation εy ~ 1.95%, a yield stress σy ~ 1650 MPa, and a Young’s modulus E ~ 84.5 GPa. The alloy shows a plastic strain εp ~ 8.0 % in a serrated plastic deformation process. Annealing induced embrittlement was observed in the relaxed BMG alloys. Comparing with the as-cast alloy, the relaxed and the composite alloys show negligible changes in elastic strain and Young’s modulus. The partially crystallized alloys are macroscopically brittle. Well developed vein patterns were observed in the fracture surfaces of all these alloys. The present work revealed that the dispersion of nanometer scaled i-phase particles is not effective as a barrier against shear localization in these partially quasicrystallized alloys.

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