Hgl-xCdxTe-Cr Interface Reaction

1984 ◽  
Vol 37 ◽  
Author(s):  
P. Philip ◽  
A. Wall ◽  
A. Franciosi ◽  
D. J. Peterman

AbstractWe summarize photoemission studies using Synchrotron Radiation of the formation of the HgCdTe-Cr interface at room temperature on in situcleaved single crystal substrates. Evidence is found of a Cr-Hg exchange reaction in the subsurface region. The surface and near surface layers appear completely depleted of mercury.

1986 ◽  
Vol 69 ◽  
Author(s):  
H. Dosch ◽  
D. C. Wack ◽  
B. W. Batterman

AbstractWe report measurement of Bragg intensities obtained from an Fe3Al(110) single crystal under the condition of total reflection. It is demonstrated that depth-resolved near-surface atomic correlations can be achieved by the independent control of both ocurring grazing angles.


1994 ◽  
Vol 354 ◽  
Author(s):  
T. Fujihana ◽  
O. Nishimura ◽  
K. Yabe ◽  
H. Hayashi ◽  
M. Iwaki

AbstractA study has been made of the chemical composition and mechanical properties of Ti+-implanted Si3N4 surface layers. Implantation of 48Ti+ was performed with doses ranging from 10 to 1017 ions cm”2 at an energy of 150 keV, and at nearly room temperature. XPS was used to analyze the depth dependence of atomic fraction and chemical bonding states of Ti+-implanted layers. The near-surface hardness was measured by a Vickers hardness tester. The friction and wear properties were measured under unlubricated conditions at room temperature using a pin on disk-plane and a block on wheel-periphery configurations, in which the pin and wheel used were AISI1045 and ASTM Wl-9, respectively. Implanted Ti-atoms formed a gaussian distribution predicted by the range theory. At the average projected range, most of Ti-atoms existed as a metallic state and TiN bonding was also formed. Oxygen and carbon were found near the surface layers. In addition to the surface peak, O-atoms accumulated in front of the average projected range of Ti. Such O-atoms formed bonds of Si-oxides and Ti-oxides. Carbon existed as a graphitic state. With increasing a Ti dose, the near-surface hardness decreased, and the wear rate increased at the running-in stage having the high friction coefficient. The steady wear attributed to the stable friction coefficient appeared after the running-in stage, although such a stable stage was not observed for unimplanted Si3N4. The mechanism for the change in mechanical properties of Si3N4 induced by Ti+-implantation will be discussed in relation to XPS characteristics.


1999 ◽  
Vol 06 (05) ◽  
pp. 829-833 ◽  
Author(s):  
S. SPELLER ◽  
M. ASCHOFF ◽  
J. KUNTZE ◽  
W. HEILAND ◽  
A. ATREI ◽  
...  

The (001) surface of a Au 3 Pd single crystal was studied with different surface analytical techniques. The main results reported about structure, composition and dynamics of the surface are based on ion scattering methods and LEED. We find segregation of Au to the surface forming a complete Au overlayer. The second layer has approximately the bulk Pd concentration. There is no evidence for chemical order in the near surface layers, i.e. Pd is randomly distributed in the lattice. The Au and Pd atoms in the first and the second layer respectively have approximately the same thermal vibrational amplitudes.


1989 ◽  
Vol 163 ◽  
Author(s):  
A. Wall ◽  
A. Raisanen ◽  
G. Haugstad ◽  
A. Franciosi

AbstractDeposition of Mn at room temperature onto atomically clean CdTe(110) surfaces yields atomic interdiffusion for metal coverages <3 angstroms with Mn atoms occupying cation sites within the surface and near-surface layers of the semiconductor. Synchrotron radiation photoemission studies with variable photoelectron escape depth indicate the formation of a relatively homogeneous semiconductor surface alloy. The highest Mn concentration observed in the alloy exceeds those obtainable with bulk crystal growth methods.


1989 ◽  
Vol 158 ◽  
Author(s):  
Jun-Ichi Takahashi ◽  
Yuichi Utsumi ◽  
Tsuneo Urisu

ABSTRACTPhotochemical etching of Si and SiO2 using synchrotron radiation (SR) is carried out. The etching rate of SiO2 is much higher than those of poly-Si and single crystal Si. The etching rate of poly-Si increases as dopant concentration decreases. These material selectivities are quite different from those for plasma- or laser-excited etching. These new phenomena in SR-stimulated etching can be explained by a reaction model that contains reaction centers that are produced by both core and binding electronic excitation of Si and fluorinated Si in the surface layers. These centers are quenched by majority carriers.


1983 ◽  
Vol 27 ◽  
Author(s):  
W.J. Choyke ◽  
R.B. Irwin ◽  
J.N. Mcgruer ◽  
J.R. Townsend ◽  
N.J. Doyle ◽  
...  

ABSTRACTCrystals of float-zone, Czochralski, and Web Si having widely differing oxygen concentrations were imrplanted at 300°K with large fluences of hydrogen. Experiments using RBS/channeling, profilometry and microscopy are reported. For room temperature implants the step-height h, the distribution of displaced atoms ND(x) and the total number of displaced atoms/cm2 (aD) are all essentially independent of the oxygen convent of the Si.


IUCrJ ◽  
2014 ◽  
Vol 1 (4) ◽  
pp. 204-212 ◽  
Author(s):  
Francesco Stellato ◽  
Dominik Oberthür ◽  
Mengning Liang ◽  
Richard Bean ◽  
Cornelius Gati ◽  
...  

A new approach for collecting data from many hundreds of thousands of microcrystals using X-ray pulses from a free-electron laser has recently been developed. Referred to as serial crystallography, diffraction patterns are recorded at a constant rate as a suspension of protein crystals flows across the path of an X-ray beam. Events that by chance contain single-crystal diffraction patterns are retained, then indexed and merged to form a three-dimensional set of reflection intensities for structure determination. This approach relies upon several innovations: an intense X-ray beam; a fast detector system; a means to rapidly flow a suspension of crystals across the X-ray beam; and the computational infrastructure to process the large volume of data. Originally conceived for radiation-damage-free measurements with ultrafast X-ray pulses, the same methods can be employed with synchrotron radiation. As in powder diffraction, the averaging of thousands of observations per Bragg peak may improve the ratio of signal to noise of low-dose exposures. Here, it is shown that this paradigm can be implemented for room-temperature data collection using synchrotron radiation and exposure times of less than 3 ms. Using lysozyme microcrystals as a model system, over 40 000 single-crystal diffraction patterns were obtained and merged to produce a structural model that could be refined to 2.1 Å resolution. The resulting electron density is in excellent agreement with that obtained using standard X-ray data collection techniques. With further improvements the method is well suited for even shorter exposures at future and upgraded synchrotron radiation facilities that may deliver beams with 1000 times higher brightness than they currently produce.


2018 ◽  
Vol 185 ◽  
pp. 10001 ◽  
Author(s):  
Elizaveta V. Golubeva ◽  
Anna A. Chlenova ◽  
Elena A. Stepanova ◽  
Galina V. Kurlyandskaya

Fe3Co66Cr3Si16B12 and Fe6Co60Ni10Si14B10 amorphous ribbons were surface modified in toluene at room temperature. Such a treatment resulted in deposition of thin carbon-based layer. As a result of the carbon covering deposition the stress distribution in the near-surface layers was changed due to partial compensation of the initial quenching stresses. Comparative analysis of magnetic and magnetoimpedance properties of as-quenched and surface modified ribbons confirms changes in effective magnetic anisotropy as a result of surface treatment. An increase of the corrosion resistance of the ribbons with carbon covering can be useful for the development amorphous ribbon based magnetic biosensor.


2006 ◽  
Vol 928 ◽  
Author(s):  
Dirk Carl Meyer ◽  
Alexandr A. Levin ◽  
Tilmann Leisegang ◽  
Emanuel Gutmann ◽  
Marianne Reibold ◽  
...  

ABSTRACTOn base of the structural characteristics of near-surface regions of a SrTiO3 (001) (STO (001)) single-crystal plate revealed by means of wide-angle X-ray scattering (WAXS), X-ray fluorescence spectroscopy and high-resolution transmission electron microscopy, structural changes in the STO (001) single-crystal plate under the influence of an external electric field at room temperature can be described as the tunable and reversible formation of Ruddlesden-Popper-phases of the quasi-binary system SrO-TiO2. The WAXS behavior implies the use of the reversible phase-transition for adaptive X-ray optics.


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