scholarly journals EVOLUTION OF A DISLOCATION STRUCTURE DURING THE GROWTH SILICON SINGLE CRYSTALS OF n- AND p-TYPE

2020 ◽  
pp. 44-50
Author(s):  
N.A. Azarenkov ◽  
V.E. Semenenko ◽  
N.G. Stervoyedov
Keyword(s):  
Phase Transformation ◽  
Single Crystals ◽  
Dislocation Structure ◽  
Semiconductor Devices ◽  
Screw Dislocations ◽  
Linear Defects ◽  
The Stability ◽  
P Type ◽  
Kinetics Of ◽  
Concentration Of Impurities

The kinetics of the formation of perfect n- and p-type silicon single crystals is considered. The peculiarity of the formation of point and linear defects in the process of a controlled phase transformation of a liquid-solid is established. The effect of supersaturation by vacancies of the direction of predominant growth and concentration of impurities on the formation and removal of edge and screw dislocations is determined. The effect of linear defects on the scattering and recombination of mobile current carriers is revealed. The possibilities of increasing the stability and efficiency of silicon semiconductor devices are discussed.

scholarly journals On the Stability of 3C-SiC Single Crystals at High Temperatures

2012 ◽  
Vol 717-720 ◽  
pp. 493-496
Author(s):  
Deborah Dompoint ◽  
Irina G. Galben-Sandulache ◽  
Alexandre Boulle ◽  
Didier Chaussende ◽  
Dominique Eyidi ◽  
...  
Keyword(s):  
Single Crystals ◽  
Volume Fraction ◽  
Diffuse Intensity ◽  
X Ray ◽  
Partial Dislocations ◽  
X Ray Scattering ◽  
Transmission Electron ◽  
The Stability ◽  
Kinetics Of ◽  
Evolution With Time

The 3C-6H polytypic transition in 3C-SiC single crystals is studied by means of diffuse X-ray scattering (DXS) coupled with transmission electron microscopy (TEM). TEM reveals that the partially transformed SiC crystals contain regions of significantly transformed SiC (characterized by a high density of stacking faults) co-existing with regions of pure 3C-SiC. The simulation of the diffuse intensity allows to determine both the volume fraction of transformed material and the transformation level within these regions. It is further shown that the evolution with time and temperature of the transition implies the multiplication and glide of partial dislocations, the kinetics of which are quantified by means of DXS.

Electronic States of Oxygen-Free Dislocation Networks Produced by Direct Bonding of Silicon Wafers

2009 ◽  
Vol 156-158 ◽  
pp. 283-288 ◽  
Author(s):  
Maxim Trushin ◽  
O.F. Vyvenko ◽  
Teimuraz Mchedlidze ◽  
Oleg Kononchuk ◽  
Martin Kittler
Keyword(s):  
Oxygen Concentration ◽  
Dislocation Structure ◽  
Electronic States ◽  
Silicon Wafers ◽  
Experimental Investigations ◽  
Deformation Potential ◽  
Screw Dislocations ◽  
Type Silicon ◽  
Frenkel Effect ◽  
P Type

The results of experimental investigations of the dislocation-related DLTS-peaks originated from the dislocation networks (DN) are presented. Samples with DNs were produced by direct bonding of p-type silicon wafers and no enhancement of oxygen concentration was detected near the DN plane. Origins of the DLTS peaks were proposed and a correlation with the dislocation-related photoluminescence data was established based on known dislocation structure of the samples. Two types of shallow DLTS peaks exhibited Pool-Frenkel effect, which could be linked to the dislocation deformation potential. One of the shallow DLTS peaks was related to straight parts of screw dislocations and another - to the intersections of the dislocations.

Electromagnetoelasticity Effect in Silicon

2017 ◽  
Vol 269 ◽  
pp. 78-89 ◽  
Author(s):  
Arkady A. Skvortsov ◽  
Andrey V. Karizin
Keyword(s):  
Magnetic Field ◽  
Activation Energy ◽  
Plastic Deformation ◽  
Electric Current ◽  
Interaction Energy ◽  
Single Crystals ◽  
Exposure Time ◽  
Constant Magnetic Field ◽  
Linear Defects ◽  
P Type

The paper is devoted to the study of the magnetostimulated dynamics of dislocations in silicon and the influence of electric current on this process. As a result of the conducted studies, it was found that preliminary exposure of n-and p-type silicon single crystals in a constant magnetic field (B = 1 T, exposure time up to 30 minutes) leads to an increase in mobility of dislocation segments in them during plastic deformation of samples (Т=675оС, σ=60–100 MPa, t=45–60 minutes). The quadratic dependence of the dislocation ranges on the induction of a constant magnetic field was found on the samples studied. A decrease in the activation characteristics of the process of displacement of linear defects during the flow of electric current during deformation is also detected: the transmission of electric current helps to reduce the activation energy of the process from 2.2± 0.2 eV to 0.7±0.1 eV. The observed changes are attributed to a decrease in the interaction energy of linear defects with dislocation stoppers based on the dopant.

Study of Deep Levels by Admittance Spectroscopy in High Resistivity P-Type 6H-SiC Single Crystals

1995 ◽  
Vol 378 ◽  
Author(s):  
A. O. Evwaraye ◽  
S. R. Smith ◽  
W. C. Mitchel
Keyword(s):  
Single Crystals ◽  
Deep Levels ◽  
High Resistivity ◽  
Admittance Spectroscopy ◽  
Donor Level ◽  
Decay Kinetics ◽  
Exponential Form ◽  
Conductance Peak ◽  
P Type ◽  
Kinetics Of

AbstractDeep levels in high resistivity p-type 6H-SiC has been studied using optical admittance spectroscopy ( OAS ). Besides the conductance peak due to the band to band transitions, there are three conductance peaks in the spectra of most of the samples. The conductance peak due to the vanadium donor (0/+) level at EV+ 1.55 eV is identified. The persistent photoconductance (PPC) at this defect was also studied. The decay kinetics of the PPC follow the stretched exponential form. The potential barrier against recapture of carriers was determined to be 220 meV for the vanadium donor level.

Influence of DC Current on Movement of Dislocations in P-Silicon Single Crystals in Field of Internal Stresses

2021 ◽  
Vol 316 ◽  
pp. 975-980
Author(s):  
Alexander A. Solovyev ◽  
Vladislav V. Rybin ◽  
Artem V. Kulagin
Keyword(s):  
Experimental Data ◽  
Relaxation Time ◽  
Single Crystals ◽  
Linear Density ◽  
Isothermal Annealing ◽  
Matching Theory ◽  
Internal Stresses ◽  
Linear Defects ◽  
P Type ◽  
Dc Current

The behavior of linear defects in p-type silicon (111) carrying a direct current of density 0−15×105 A/m2 in the [110] direction are studied in the temperature range T=850–1000 K during isothermal annealing. The regularities of change in the linear density and maximum path of dislocations in slip lines are revealed. A model of linear defects displacement in silicon single crystals in the field of internal stresses under an electric current is proposed. Matching theory with experimental data has made it possible to reveal the dependence of this distribution on the internal stresses relaxation time.

scholarly journals Interpretations of Cooling Dilatograms in the Range of the Bainitic and Martensitic Transformations/ Intwerpretacja Dylatogramów Chłodzenia W Zakresie Przemiany Bainitycznej I Martenzytycznej

2014 ◽  
Vol 59 (4) ◽  
pp. 1679-1683 ◽  
Author(s):  
J. Pacyna
Keyword(s):  
Phase Transformation ◽  
Phase Transformations ◽  
Martensitic Transformations ◽  
Lower Bainite ◽  
Correct Interpretation ◽  
Dilatometric Curve ◽  
Treatment Technologies ◽  
The Stability ◽  
Kinetics Of ◽  
Undercooled Austenite

Abstract The method of interpretation of cooling dilatograms of undercooled austenite during its transformation into upper and lower bainite (UB and LB) and into martensite (M), applied in the Laboratory of Phase Transformations of AGH University of Science and Technology in Krakow, is presented in the hereby paper. The relation of the mechanism of the mentioned above transformations to places on the dilatometric curve where transformations start and where they are continued was indicated. An appeal for the unified, correct interpretation of dilatograms of phase transformations, in all laboratories of the world, was formulated. This will allow the formation of equally accurate diagrams of the kinetics of phase transformation of undercooled austenite at its continuous cooling (CCT). In consequence, this could provide a development of more advanced heat treatment technologies. Such approach will also allow for the correct assessment of the influence of the alloying elements on the stability of austenite and phase transformation temperatures at its cooling.

Bright field and weak-beam images of dislocations gliding on (001) planes in F.C.C. metals

1978 ◽  
Vol 36 (1) ◽  
pp. 352-353
Author(s):  
H. P. Karnthaler ◽  
A. Korner
Keyword(s):  
Single Crystals ◽  
Dislocation Structure ◽  
Room Temperature ◽  
Stage Ii ◽  
Bright Field ◽  
Weak Beam ◽  
Standard Orientation

In f.c.c. metals slip is observed to occur generally on {111} planes. Glide dislocations on intersecting {111} planes can react with each other and form Lomer-Cottrell locks which lie along a <110> direction and are sessile since they are split on two {111} planes. Cottrell already pointed out that these dislocations could glide on {001} planes if they were not split. The first study of this phenomenon has been published recently. It is the purpose of this paper to report some interesting new details of the dislocations gliding on {001} planes in pure Ni, Cu, and Ag deformed at room temperature.Single crystals are grown with standard orientation and strained into stage II. The crystals are sliced parallel to the (001) planes. The dislocation structure is studied by TEM and the Burgers vectors ḇ and glide planes of the dislocations are determined unambiguously.In Fig.l primary P and secondary S dislocations react and form composite dislocations K.

The stability of dislocation networks under various oxygen-doping conditions in superconducting Bi2Sr2CaCu2Oy single crystals and their influence on the flux pinning properties

1994 ◽  
Vol 52 ◽  
pp. 802-803
Author(s):  
Y. Feng ◽  
X. Y. Cai ◽  
R. J. Kelley ◽  
D. C. Larbalestier
Keyword(s):  
Single Crystals ◽  
Oxygen Content ◽  
Basal Plane ◽  
Flux Pinning ◽  
Pinning Centers ◽  
Before And After ◽  
Anomalous Peak ◽  
Basal Plane Dislocation ◽  
The Stability ◽  
Further Development

The issue of strong flux pinning is crucial to the further development of high critical current density Bi-Sr-Ca-Cu-O (BSCCO) superconductors in conductor-like applications, yet the pinning mechanisms are still much debated. Anomalous peaks in the M-H (magnetization vs. magnetic field) loops are commonly observed in Bi2Sr2CaCu2Oy (Bi-2212) single crystals. Oxygen vacancies may be effective flux pinning centers in BSCCO, as has been found in YBCO. However, it has also been proposed that basal-plane dislocation networks also act as effective pinning centers. Yang et al. proposed that the characteristic scale of the basal-plane dislocation networksmay strongly depend on oxygen content and the anomalous peak in the M-H loop at ˜20-30K may be due tothe flux pinning of decoupled two-dimensional pancake vortices by the dislocation networks. In light of this, we have performed an insitu observation on the dislocation networks precisely at the same region before and after annealing in air, vacuumand oxygen, in order to verify whether the dislocation networks change with varying oxygen content Inall cases, we have not found any noticeable changes in dislocation structure, regardless of the drastic changes in Tc and the anomalous magnetization. Therefore, it does not appear that the anomalous peak in the M-H loops is controlled by the basal-plane dislocation networks.

Kinetics of Various 99mTc-Sn-Pyrophosphate Compounds in the Rat

1977 ◽  
Vol 16 (04) ◽  
pp. 157-162 ◽  
Author(s):  
C. Schümichen ◽  
B. Mackenbrock ◽  
G. Hoffmann
Keyword(s):  
Normal Saline ◽  
Half Life ◽  
Compound A ◽  
Short Half Life ◽  
Low Concentrations ◽  
The Stability ◽  
Kinetics Of ◽  
In Vitro Stability

SummaryThe bone-seeking 99mTc-Sn-pyrophosphate compound (compound A) was diluted both in vitro and in vivo and proved to be unstable both in vitro and in vivo. However, stability was much better in vivo than in vitro and thus the in vitro stability of compound A after dilution in various mediums could be followed up by a consecutive evaluation of the in vivo distribution in the rat. After dilution in neutral normal saline compound A is metastable and after a short half-life it is transformed into the other 99mTc-Sn-pyrophosphate compound A is metastable and after a short half-life in bone but in the kidneys. After dilution in normal saline of low pH and in buffering solutions the stability of compound A is increased. In human plasma compound A is relatively stable but not in plasma water. When compound B is formed in a buffering solution, uptake in the kidneys and excretion in urine is lowered and blood concentration increased.It is assumed that the association of protons to compound A will increase its stability at low concentrations while that to compound B will lead to a strong protein bond in plasma. It is concluded that compound A will not be stable in vivo because of a lack of stability in the extravascular space, and that the protein bond in plasma will be a measure of its in vivo stability.

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