scholarly journals Observation of Superheating of Si at the Si/SiO2 Interface in Pulsed-laser irradiated Si Thin Films

2015 ◽  
Vol 1770 ◽  
pp. 43-48
Author(s):  
J.J. Wang ◽  
A.B. Limanov ◽  
Ying Wang ◽  
James S. Im
Keyword(s):  
Single Crystal ◽  
Quartz Substrate ◽  
Incident Beam ◽  
Melting Transition ◽  
Back Side ◽  
Excimer Laser Pulse ◽  
Solid Film ◽  
The One ◽  
Si Films

ABSTRACTSubstantial superheating of single-crystal Si films at and near the bottom Si/SiO2 interface was observed. This was accomplished via back-side irradiation of a (100) single-crystal Si film on a quartz substrate using an excimer-laser pulse. The spatiotemporal details of the melting transition were tracked in situ using surface-side and substrate-side transient reflectance measurements, and the one-dimensional thermal profile evolution within the solid film during the heating period was numerically computed using the experimentally extracted temporal profile of the incident beam and temperature-dependent optical and thermal parameters of the materials. A simple lower-bound estimation identifies that superheating in excess of 100 K was attained within Si along the bottom (100)-Si/SiO2 interface even at moderate beam energy densities.

Dependence of Crystallographic Texture of C54 Tisi2 on Thickness and Linewidth In Submicron Cmos Structures

1996 ◽  
Vol 427 ◽  
Author(s):  
V. Svilan ◽  
K. P. Rodbell ◽  
L. A. Clevenger ◽  
C. Cabral ◽  
R. A. Roy ◽  
...  
Keyword(s):  
Single Crystal ◽  
Single Crystal Silicon ◽  
Ex Situ ◽  
X Ray Diffraction ◽  
Crystal Silicon ◽  
The One ◽  
Oriented Parallel ◽  
Preferential Crystal Orientation ◽  
Line Direction

AbstractPreferential crystal orientation of low-resistance C54 TiSi2 formed in the reaction of polycrystalline and single crystal silicon with titanium was investigated for Ti thicknesses ranging from 15 to 44 nm. Using in situ synchrotron x-ray diffraction during heating of 15 nm of Ti on single crystal Si, we observed that the C54 TiSi2 silicide film showed predominantly <040> grains oriented normal to the sample. In thicker silicide films the <311> orientation dominated or film was randomly oriented. An ex situ four circle diffractometer was used to investigate the strong <040> texture in narrow line arrays of C54-TiSi2 formed on polycrystalline silicon with linewidths from 0.2 to 1.1 μm. We observed that the angular distribution of <040> Ti Si2 grains is dependent on the line direction, where the majority of grains had their (100) planes oriented parallel with the line direction. These findings support a model of the C49 to C54 TiSi2 transformation involving rapid growth of certain orientations favored by the one-dimensional geometry imposed by narrow lines.

Properties of Single-Crystal Silicon Films on Amorphous SiO2 on Single-Crystal Cubic Zirconia Substrates

1985 ◽  
Vol 48 ◽  
Author(s):  
I. Golecki ◽  
R. L. Maddox ◽  
H. L. Glass ◽  
A. L. Lin ◽  
H. M. Manasevit
Keyword(s):  
Single Crystal ◽  
Single Crystal Silicon ◽  
Silicon On Insulator ◽  
Back Side ◽  
X Ray Diffraction ◽  
Large Area ◽  
Crystal Silicon ◽  
Amorphous Sio2 ◽  
Cubic Zirconia ◽  
Si Films

ABSTRACTA new approach to achieving a large-area silicon-on-insulator technology without pre-patterning is described. (100) Si films are first grown epitaxially on (100) yttria-stabilized cubic zirconia (YSZ) substrates by the pyrolysis of SiH4. The Si side of the <Si>/<YSZ>interface is then oxidized in pyrogenic steam (at 925 °C) or dry oxygen (at 1100°C) to form the structure <Si>/amorphous SiO2/<YSZ>. The oxidation occurs by the rapid diffusion of oxidants through the 0.42 mm thick YSZ substrate; e.g., a 0.3 μm SiO2 layer is obtained in 6 h in steam. The samples are analyzed by Rutherford backscattering and channeling spectrometry, X-ray diffraction, infra-red reflectance, Auger electron spectroscopy and sheet resistance measurements. In addition to forming the preferred Si/SiO2 interface, the back-side oxidation eliminates the most defective part of the Si film.

Structure of Palladium Single-Crystal Films Prepared by Flash Evaporation onto (001) NaCl Substrates

1970 ◽  
Vol 28 ◽  
pp. 456-457
Author(s):  
L. E. Murr ◽  
G. Wong
Keyword(s):  
Single Crystal ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
High Rate ◽  
Flash Evaporation ◽  
Optimum Load ◽  
Single Crystal Films ◽  
Crystal Films ◽  
A Current

Palladium single-crystal films have been prepared by Matthews in ultra-high vacuum by evaporation onto (001) NaCl substrates cleaved in-situ, and maintained at ∼ 350° C. Murr has also produced large-grained and single-crystal Pd films by high-rate evaporation onto (001) NaCl air-cleaved substrates at 350°C. In the present work, very large (∼ 3cm2), continuous single-crystal films of Pd have been prepared by flash evaporation onto air-cleaved (001) NaCl substrates at temperatures at or below 250°C. Evaporation rates estimated to be ≧ 2000 Å/sec, were obtained by effectively short-circuiting 1 mil tungsten evaporation boats in a self-regulating system which maintained an optimum load current of approximately 90 amperes; corresponding to a current density through the boat of ∼ 4 × 104 amperes/cm2.

Towards quantitative simulations of inelastic electron diffraction patterns and images

1992 ◽  
Vol 50 (2) ◽  
pp. 1170-1171
Author(s):  
Z. L. Wang
Keyword(s):  
Phonon Scattering ◽  
Incident Beam ◽  
Dynamical Theory ◽  
Inelastic Electron ◽  
Additional Advantage ◽  
Coupled Equations ◽  
Atomic Vibrations ◽  
Diffraction Patterns ◽  
Primary Advantage ◽  
The One

A new dynamical theory has been developed based on Yoshioka's coupled equations for describing inelastic electron scattering in thin crystals. Compared to existing theories, the primary advantage of this theory is that the incoherent summation of the diffracted intensities contributed by electrons after exciting vast numbers of different excited states has been evaluated before any numerical calculation. An additional advantage is that the phase correlations of atomic vibrations are considered, so that full lattice dynamics can be combined in the phonon scattering calculation. The new theory has been proven to be equivalent to the inelastic multislice theory, and has been applied to calculate energy-filtered diffraction patterns and images formed by phonon, single electron and valence scattered electrons.A calculated diffraction pattern of elastic and phonon scattered electrons for a parallel incident beam case is in agreement with the one observed (Fig. 1), showing thermal diffuse scattering (TDS) streaks and Kikuchi pattern.

Single Crystal Growth of High-Pressure Phases of Ice and Salt Hydrate Far Below the Original Melting Point by Mixing Alcohol: Crystal Structure Determination of Magnesium Chloride Heptahydrate

2020 ◽  
Author(s):  
Keishiro Yamashita ◽  
Kazuki Komatsu ◽  
Hiroyuki Kagi
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Crystal Growth ◽  
Single Crystal ◽  
Room Temperature ◽  
Growth Technique ◽  
Salt Hydrate ◽  
X Ray

An crystal-growth technique for single crystal x-ray structure analysis of high-pressure forms of hydrogen-bonded crystals is proposed. We used alcohol mixture (methanol: ethanol = 4:1 in volumetric ratio), which is a widely used pressure transmitting medium, inhibiting the nucleation and growth of unwanted crystals. In this paper, two kinds of single crystals which have not been obtained using a conventional experimental technique were obtained using this technique: ice VI at 1.99 GPa and MgCl<sub>2</sub>·7H<sub>2</sub>O at 2.50 GPa at room temperature. Here we first report the crystal structure of MgCl2·7H2O. This technique simultaneously meets the requirement of hydrostaticity for high-pressure experiments and has feasibility for further in-situ measurements.

scholarly journals NIR responsive tumor vaccine in situ for photothermal ablation and chemotherapy to trigger robust antitumor immune responses

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Lirong Zhang ◽  
Jingjing Zhang ◽  
Lixia Xu ◽  
Zijian Zhuang ◽  
Jingjin Liu ◽  
...  
Keyword(s):  
Immune Responses ◽  
Tumor Vaccine ◽  
Oxidative Polymerization ◽  
Delivery Mode ◽  
Tumor Treatment ◽  
One Pot ◽  
Photothermal Ablation ◽  
Prolonged Retention ◽  
The One

Abstract Background Therapeutic tumor vaccine (TTV) that induces tumor-specific immunity has enormous potentials in tumor treatment, but high heterogeneity and poor immunogenicity of tumor seriously impair its clinical efficacy. Herein, a novel NIR responsive tumor vaccine in situ (HA-PDA@IQ/DOX HG) was prepared by integrating hyaluronic acid functionalized polydopamine nanoparticles (HA-PDA NPs) with immune adjuvants (Imiquimod, IQ) and doxorubicin (DOX) into thermal-sensitive hydrogel. Results HA-PDA@IQ NPs with high photothermal conversion efficiency (41.2%) and T1-relaxation efficiency were using HA as stabilizer by the one-pot oxidative polymerization. Then, HA-PDA@IQ loaded DOX via π-π stacking and mixed with thermal-sensitive hydrogel to form the HA-PDA@IQ/DOX HG. The hydrogel-confined delivery mode endowed HA-PDA@IQ/DOX NPs with multiple photothermal ablation performance once injection upon NIR irradiation due to the prolonged retention in tumor site. More importantly, this mode enabled HA-PDA@IQ/DOX NPs to promote the DC maturation, memory T cells in lymphatic node as well as cytotoxic T lymphocytes in spleen. Conclusion Taken together, the HA-PDA@IQ/DOX HG could be served as a theranostic tumor vaccine for complete photothermal ablation to trigger robust antitumor immune responses.

Laser damage mechanism and in-situ observation of stacking fault relaxation in β-Ga2O3 single crystal by EFG method

CrystEngComm ◽  
2021 ◽  
Author(s):  
Bo Fu ◽  
Gaohang He ◽  
Wenxiang Mu ◽  
Yang Li ◽  
Boyuan Feng ◽  
...  
Keyword(s):  
Single Crystal ◽  
Light Field ◽  
Damage Mechanism ◽  
Stacking Fault ◽  
High Light ◽  
Laser Damage ◽  
In Situ Observation ◽  
Structure Destruction

We designed an original and effective method to study the laser damage mechanism of β-Ga2O3 single crystal grown by edge-defined film-fed growth (EFG). The structure destruction under high light field...

In-situ X-ray tomography investigation of pore damage effects during a tensile test of a Ni-based single crystal superalloy

2021 ◽  
pp. 111180
Author(s):  
Keli Liu ◽  
Junsheng Wang ◽  
Bing Wang ◽  
Pengcheng Mao ◽  
Yanhong Yang ◽  
...  
Keyword(s):  
Tensile Test ◽  
Single Crystal ◽  
Single Crystal Superalloy ◽  
X Ray

scholarly journals Crack Propagation Behavior of a Ni-Based Single-Crystal Superalloy during In Situ SEM Tensile Test at 1000 °C

Crystals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1047
Author(s):  
Wenxiang Jiang ◽  
Xiaoyi Ren ◽  
Jinghao Zhao ◽  
Jianli Zhou ◽  
Jinyao Ma ◽  
...  
Keyword(s):  
Crack Propagation ◽  
Tensile Test ◽  
Single Crystal ◽  
Crack Propagation Rate ◽  
Propagation Rate ◽  
Single Crystal Superalloy ◽  
Propagation Path ◽  
Propagation Behavior ◽  
Crack Propagation Behavior

An in situ scanning electron microscope (SEM) tensile test for Ni-based single-crystal superalloy was carried out at 1000 °C. The stress displacement was obtained, and the yield strength and tensile strength of the superalloy were 699 MPa and 826 MPa, respectively. The crack propagation process, consisting of Model I crack and crystallographic shearing crack, was determined. More interestingly, the crack propagation path and rate affected by eutectics was directly observed and counted. Results show that the coalescence of the primary crack and second microcrack at the interface of a γ/γ′ matrix and eutectics would make the crack propagation rate increase from 0.3 μm/s to 0.4 μm/s. On the other hand, crack deflection decreased the rate to 0.05 μm/s. Moreover, movement of dislocations in front of the crack was also analyzed to explain the different crack propagation behavior in the superalloy.

scholarly journals Two Separate Cases: Complex Chromosomal Abnormality Involving Three Chromosomes and Small Supernumerary Marker Chromosome in Patients with Impaired Reproductive Function

Genes ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1511
Author(s):  
Tatyana V. Karamysheva ◽  
Tatyana A. Gayner ◽  
Vladimir V. Muzyka ◽  
Konstantin E. Orishchenko ◽  
Nikolay B. Rubtsov
Keyword(s):  
Genetic Counseling ◽  
Chromosome Rearrangement ◽  
Marker Chromosome ◽  
Reproductive Function ◽  
Small Supernumerary Marker Chromosome ◽  
Comprehensive Chromosome Screening ◽  
The Family ◽  
Multicolor Banding ◽  
The One

For medical genetic counseling, estimating the chance of a child being born with chromosome abnormality is crucially important. Cytogenetic diagnostics of parents with a balanced karyotype are a special case. Such chromosome rearrangements cannot be detected with comprehensive chromosome screening. In the current paper, we consider chromosome diagnostics in two cases of chromosome rearrangement in patients with balanced karyotype and provide the results of a detailed analysis of complex chromosomal rearrangement (CCR) involving three chromosomes and a small supernumerary marker chromosome (sSMC) in a patient with impaired reproductive function. The application of fluorescent in situ hybridization, microdissection, and multicolor banding allows for describing analyzed karyotypes in detail. In the case of a CCR, such as the one described here, the probability of gamete formation with a karyotype, showing a balance of chromosome regions, is extremely low. Recommendation for the family in genetic counseling should take into account the obtained result. In the case of an sSMC, it is critically important to identify the original chromosome from which the sSMC has been derived, even if the euchromatin material is absent. Finally, we present our view on the optimal strategy of identifying and describing sSMCs, namely the production of a microdissectional DNA probe from the sSMC combined with a consequent reverse painting.

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