scholarly journals Study of Detector-Grade CdMnTe:In Crystals Obtained by a Multi-Step Post-Growth Annealing Method

Crystals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 387 ◽  
Author(s):  
Pengfei Yu ◽  
Yongren Chen ◽  
Wei Li ◽  
Wenfei Liu ◽  
Bin Liu ◽  
...  
Keyword(s):  
Annealing Temperature ◽  
Crystal Quality ◽  
High Resistivity ◽  
Detector Performance ◽  
Rocking Curve ◽  
X Ray ◽  
Annealing Step ◽  
Subsequent Step ◽  
Te Inclusions ◽  
Annealing Method

A multi-step annealing method was successfully applied to inclusions reduction and resistivity improvement of CdMnTe:In (CMT:In) single crystals with high resistivity, including a Cd atmosphere annealing step followed by a Te atmosphere annealing step. After the Cd atmosphere annealing step, the density of Te inclusions was reduced distinctly, and it could be also decreased in the subsequent step of re-annealing under Te atmosphere. Both the resistivity and IR transmittance decreased notably after Cd atmosphere annealing, whereas they increased tremendously after re-annealing under a Te atmosphere. The reduction of full-width at-half-maximum (FWHM) and the increase of the intensity of the X-ray rocking curve indicated an improvement of the crystal quality. Meanwhile, after Cd atmosphere annealing, the increase of the intensity of the (D0,X) peak and the disappearance of the (A0,X) peak in photoluminescence (PL) measurements suggested further that the crystal quality was improved. The detector performance was enhanced obviously after annealing. The higher the annealing temperature, the better the performance was. The detector fabricated by CMT:In slice (Cd atmosphere annealing at 1073 K for 240 h and Te atmosphere re-annealing at 773 K for 120 h) with 9.43% energy resolution and 1.25 × 10−3 cm2/V μτ value had the best detector performance.

Doped ZnO Nanowires Obtained by Thermal Annealing

2007 ◽  
Vol 7 (2) ◽  
pp. 700-703 ◽  
Author(s):  
C. X. Shan ◽  
Z. Liu ◽  
C. C. Wong ◽  
S. K. Hark
Keyword(s):  
Thermal Annealing ◽  
Doping Concentration ◽  
Annealing Temperature ◽  
Zno Nanowires ◽  
X Ray Diffraction ◽  
X Ray ◽  
Doped Zno ◽  
Znse Nanowires ◽  
Annealing Method ◽  
Scanning Electron

Doped ZnO nanowires were prepared in a very simple and inexpensive thermal annealing method using ZnSe nanowires as a precursor. As doped, P doped, and As/P codoped ZnO nanowires were obtained in this method. X-ray diffraction shows that the zincblende ZnSe nanowires were converted to doped wurtzite ZnO nanowires. The incorporation of the dopants was confirmed by energy dispersive X-ray spectroscopy. The doping concentration could be adjusted by changing the annealing temperature and duration. Scanning electron microscopy indicated that the morphology of the ZnSe nanowires was essentially retained after the annealing and doping process. Photoluminescence spectroscopy also verified the incorporation of the dopants into the nanowires.

Doped ZnO Nanowires Obtained by Thermal Annealing

2007 ◽  
Vol 7 (2) ◽  
pp. 700-703
Author(s):  
C. X. Shan ◽  
Z. Liu ◽  
C. C. Wong ◽  
S. K. Hark
Keyword(s):  
Thermal Annealing ◽  
Doping Concentration ◽  
Annealing Temperature ◽  
Zno Nanowires ◽  
X Ray Diffraction ◽  
X Ray ◽  
Doped Zno ◽  
Znse Nanowires ◽  
Annealing Method ◽  
Scanning Electron

Doped ZnO nanowires were prepared in a very simple and inexpensive thermal annealing method using ZnSe nanowires as a precursor. As doped, P doped, and As/P codoped ZnO nanowires were obtained in this method. X-ray diffraction shows that the zincblende ZnSe nanowires were converted to doped wurtzite ZnO nanowires. The incorporation of the dopants was confirmed by energy dispersive X-ray spectroscopy. The doping concentration could be adjusted by changing the annealing temperature and duration. Scanning electron microscopy indicated that the morphology of the ZnSe nanowires was essentially retained after the annealing and doping process. Photoluminescence spectroscopy also verified the incorporation of the dopants into the nanowires.

Improvement of crystal quality for tetragonal hen egg white lysozyme crystals under application of an external alternating current electric field

2013 ◽  
Vol 46 (1) ◽  
pp. 25-29 ◽  
Author(s):  
H. Koizumi ◽  
S. Uda ◽  
K. Fujiwara ◽  
M. Tachibana ◽  
K. Kojima ◽  
...  
Keyword(s):  
Electric Field ◽  
Egg White ◽  
Crystal Quality ◽  
Hen Egg White Lysozyme ◽  
X Ray Diffraction ◽  
Rocking Curve ◽  
X Ray ◽  
Egg White Lysozyme ◽  
Ac Electric Field ◽  
Hen Egg White

X-ray diffraction rocking-curve measurements were performed on tetragonal hen egg white lysozyme (HEWL) crystals grown with and without application of an external alternating current (AC) electric field, and then the crystal quality was assessed by the FWHMs of each rocking-curve profile. The FWHMs for HEWL crystals grown with an external electric field were smaller than those for crystals grown without. In particular, the average FWHM for the 12 12 0 reflection with an external electric field (0.0034°) was significantly smaller than that without (0.0061°). This indicates that the crystal quality of HEWL crystals was improved by application of the external AC electric field. This crystallization technique can be expected to enhance the resolution of protein molecule structure analysis by X-ray diffraction.

scholarly journals Improvement of Crystal Quality of AlN Films with Different Polarities by Annealing at High Temperature

Micromachines ◽  
2022 ◽  
Vol 13 (1) ◽  
pp. 129
Author(s):  
Yang Yue ◽  
Maosong Sun ◽  
Jie Chen ◽  
Xuejun Yan ◽  
Zhuokun He ◽  
...  
Keyword(s):  
High Temperature ◽  
Photoelectron Spectroscopy ◽  
Annealing Temperature ◽  
Nitrogen Atmosphere ◽  
Crystal Quality ◽  
X Ray ◽  
Aln Film ◽  
Key Factor ◽  
Deep Ultraviolet

High-quality AlN film is a key factor affecting the performance of deep-ultraviolet optoelectronic devices. In this work, high-temperature annealing technology in a nitrogen atmosphere was used to improve the quality of AlN films with different polarities grown by magnetron sputtering. After annealing at 1400–1650 °C, the crystal quality of the AlN films was improved. However, there was a gap between the quality of non-polar and polar films. In addition, compared with the semi-polar film, the quality of the non-polar film was more easily improved by annealing. The anisotropy of both the semi-polar and non-polar films decreased with increasing annealing temperature. The results of Raman spectroscopy, scanning electron microscopy and X-ray photoelectron spectroscopy revealed that the annihilation of impurities and grain boundaries during the annealing process were responsible for the improvement of crystal quality and the differences between the films with different polarities.

X-Ray Rocking Curve Characterization of SiC Substrates

2008 ◽  
Vol 600-603 ◽  
pp. 361-364
Author(s):  
Murugesu Yoganathan ◽  
Ping Wu ◽  
Ilya Zwieback
Keyword(s):  
Growth Process ◽  
Crystal Quality ◽  
Nondestructive Technique ◽  
Lattice Curvature ◽  
Rocking Curve ◽  
X Ray ◽  
Typical Variation

X-ray rocking curve characterization is a relatively fast and nondestructive technique that can be utilized to evaluate the crystal quality of SiC substrates. The contribution of lattice curvature to rocking curve broadening is estimated, and shown to be the major contribution to the measured broadening (FWHM). The feedback on lattice quality is used to optimize our SiC growth process. In the optimized growth runs, the typical variation in rocking curve sample angle Ω across the entire 3” diameter wafer is about 0.2 degrees. Possible mechanisms leading to changes in the lattice curvature are discussed.

Effect of Annealing Temperature on SiC Wafer Bow and Warp

2008 ◽  
Vol 1069 ◽  
Author(s):  
Xueping Xu ◽  
Chris Martin
Keyword(s):  
Thermal Annealing ◽  
Annealing Temperature ◽  
Mechanical Damage ◽  
Surface Damage ◽  
Diamond Grit ◽  
X Ray ◽  
Commercial Grade ◽  
Single Side ◽  
Annealing Step ◽  
Sic Wafer

ABSTRACTSingle-side polished silicon carbide wafers could exhibit large bow and warp due to the presence of mechanical damage on the unpolished surface. In this study, we investigated the effect of thermal annealing on the wafer bow. Two commercial-grade, double-side polished 3¡¨ 6H SiC wafers with the bow less than 5 μm were lapped using 12 μm diamond grit. One wafer was lapped on the C-face and another on the Si-face. The lapped wafers were subjected to annealing in vacuum at temperatures between 500¢XC and 2040¢XC. The wafer bow and x-ray rocking curves were measured prior to annealing and after each annealing step in order to evaluate the extent of the surface damage and degree of healing. Thermal annealing led to a decrease in the wafer bow and sharpening of the x-ray rocking curves. However, the wafer bow generated by lapping was not completely removed until annealing temperature reached ∼2000°C.

Effect of Annealing on Dielectric Property in Ni1-xCoxFe2O4 Nanoparticles Synthesized Using Albumen (egg white)

2009 ◽  
Vol 6 ◽  
pp. 205-213 ◽  
Author(s):  
S. Marutha Senthil ◽  
R. Jayaprakash ◽  
Sarabu Ramana Murthy ◽  
A.R. Phani ◽  
V.N. Singh ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Particle Size ◽  
Dielectric Constant ◽  
Dielectric Property ◽  
Annealing Temperature ◽  
Interfacial Polarization ◽  
Egg White ◽  
High Resistivity ◽  
Thermal Evaporation Method ◽  
X Ray

The nano crystalline nickel-cobalt ferrite using albumen (egg white) is synthesized by thermal evaporation method and its dielectric behaviour is analyzed for different annealing temperatures. The dielectric property of the sample is measured using impedance analyzer in the frequency range 1-100 MHz. The variation of dielectric constant and dissipation factor under different frequency for the samples at different annealing temperature are analyzed. A steady dielectric constant is observed for the sample annealed at 500°C. The dielectric constant obtained for this sample is low and it is in the range of 18.9 to 6.9 for different frequencies. This low value of dielectric constant shows the less interfacial polarization due to high resistivity which may be to the presence of a few Fe2+ ions. It is observed that the dispersion in dielectric constant by varying the annealing temperature is producing an intended result. The presence of constituent phases in Ni1-xCoxFe2O4 is confirmed by X-Ray Diffraction. The particle size for Ni1-xCoxFe2O4 obtained from Scherrer equation is found to be is 30nm. The morphology, particle size and percentage composition of elements are measured by employing Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Analysis spectrum (EDX).

Preparation and Characterization of Bi2VO5.5 Films by MOD Method

1998 ◽  
Vol 541 ◽  
Author(s):  
E Tokumitsu ◽  
Y. Takahashi ◽  
H. Ishiwara
Keyword(s):  
Dielectric Constant ◽  
Field Effect ◽  
Annealing Temperature ◽  
Field Effect Transistors ◽  
Relative Dielectric Constant ◽  
Full Width ◽  
X Ray Diffraction ◽  
Rocking Curve ◽  
X Ray

AbstractWe report the preparation and characterization of Bi2VO5.5(BVO) films grown on SrTiO3, Pt/SiO2/Si, and n-Si(100) substrates by the MOD technique. Since a dielectric constant of BVO is much lower than that of PZT or SBT, BVO is one of the promising candidates for metal-ferroelectric-semiconductor field-effect transistors (MFSFETs). It is found by X-ray diffraction (XRD) measurements that highly (001)-oriented BVO films were obtained and that the crystalline quality was improved with increasing the annealing temperature. The full width at half maximum (FWHM) in the X-ray rocking curve measurements for BVO films on SrTiO3, Pt/SiO2/Si, and n-Si(100) substrates are 0.60, 1.00, and 5.10, respectively. Electrical properties were measured with Pt top electrodes and the typical relative dielectric constant determined by the C-V characteristics is 60-80.

X-ray diffraction properties of curved crystal diffractors

1992 ◽  
Vol 50 (2) ◽  
pp. 1734-1735
Author(s):  
W. Z. Chang ◽  
D. B. Wittry
Keyword(s):  
Diffraction Theory ◽  
X Rays ◽  
Diffraction Image ◽  
X Ray Diffraction ◽  
Rocking Curve ◽  
X Ray ◽  
Bent Crystal ◽  
Diffraction Geometry ◽  
Crystal Parameter ◽  
Quantitative Procedure

Since Du Mond and Kirkpatrick first discussed the principle of a bent crystal spectrograph in 1930, curved single crystals have been widely utilized as spectrometric monochromators as well as diffractors for focusing x rays diverging from a point. Curved crystal diffraction theory predicts that the diffraction parameters - the rocking curve width w, and the peak reflection coefficient r of curved crystals will certainly deviate from those of their flat form. Due to a lack of curved crystal parameter data in current literature and the need for optimizing the choice of diffraction geometry and crystal materials for various applications, we have continued the investigation of our technique presented at the last conference. In the present abstract, we describe a more rigorous and quantitative procedure for measuring the parameters of curved crystals.The diffraction image of a singly bent crystal under study can be obtained by using the Johann geometry with an x-ray point source.

High-purity Ge x-ray detectors: Sensitivity factors and usefulness

1990 ◽  
Vol 48 (2) ◽  
pp. 548-548
Author(s):  
E. B. Steel
Keyword(s):  
High Purity ◽  
High Energy ◽  
Quantitative Chemical Analysis ◽  
Detector Performance ◽  
X Ray ◽  
Detector Sensitivity ◽  
Specimen Holder ◽  
Many Instruments ◽  
Charge Resolution ◽  
Sensitivity Factors

High Purity Germanium (HPGe) x-ray detectors are now commercially available for the analytical electron microscope (AEM). The detectors have superior efficiency at high x-ray energies and superior resolution compared to traditional lithium-drifted silicon [Si(Li)] detectors. However, just as for the Si(Li), the use of the HPGe detectors requires the determination of sensitivity factors for the quantitative chemical analysis of specimens in the AEM. Detector performance, including incomplete charge, resolution, and durability has been compared to a first generation detector. Sensitivity factors for many elements with atomic numbers 10 through 92 have been determined at 100, 200, and 300 keV. This data is compared to Si(Li) detector sensitivity factors.The overall sensitivity and utility of high energy K-lines are reviewed and discussed. Many instruments have one or more high energy K-line backgrounds that will affect specific analytes. One detector-instrument-specimen holder combination had a consistent Pb K-line background while another had a W K-line background.

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