Complex study of H-induced structural rearrangements in FeZr glasses

Microstructural changes and relaxation processes were examined in Fe-Zr based rapidly solidified samples. These phenomena occur far below crystallization temperature in the course of heat treatment, or even at room temperature, induced by absorbed hydrogen

Sputtered nanocrystalline ceramic TiC / amorphous C thin films as potential materials for medical applications

The relationship between structural behaviour of sp uttered TiC / amorphous C (TiC /a:C) thin films and corrosion properties was measured in thre e various pH solutions (0.5 M NaCl (pH=6); 0.1 M HCl (pH=1); 0.1 M NaOH (pH=13). The ~ 400 nm thick nanocomposites were deposited by DC magnetron sputtering on different s ubstrates (Ti6Al4V alloy and CoCrMo alloy) in argon at 25 C° and 0.25 Pa with 150 W inp ut power of carbon target and 50 W input power of titanium target. The structure and composi tion of nanocomposites were investigated by Transmission and Scanning Electron Microscopy. I n both samples the structural investigations confirmed columnar structure of TiC /a:C films with 25-50 nm sized cubic TiC. These columns were separated by 2 - 3 nm thin amorp hous carbon layers. TiC /a:C /Ti6Al4V alloy implant material showed better corrosion resi stance than the TiC /a:C /CoCrMo alloy in 0.5 M NaCl solution based on results of the Electro chemical Impedance Spectroscopy. For both samples, the 0.1 M NaOH solution was the most corrosive media

The Contact Angle Between Ag-Based Melts and Graphite Substrate and the Texture Evolution During the Subsequent Solidification

Ag based alloys are widely used in the modern brazing technologies for the substitution of tin-lead based alloys. In the present work the wetting ability between graphite substrate and diluted Ag-M (M: Cd, In, Sn, Sb) has been studied using the sessile drop method. The contact angle between the liquids and solid substrate was measured at 1200˚C. Subsequently the micro structure of the solidified drops was investigated applying X-ray diffraction (XRD) and transmission electron microscopic (TEM) measurements. A texture formation was found in the substrate/drop interface region. Comparing the values of the contact angles measured on the Ag- M samples with the degree of the texture determined by XRD it was found, that the contact angle is smaller the degree of texture higher

Determination of the Complex Dielectric Function of Ion-Implanted Amorphous Germanium by Spectroscopic Ellipsometry

Accurate reference dielectric functions play an important role in the research and development of optical materials. Libraries of such data are required in many applications in which amorphous semiconductors are gaining increasing interest, such as in integrated optics, optoelectronics or photovoltaics. The preparation of materials of high optical quality in a reproducible way is crucial in device fabrication. In this work, amorphous Ge (a-Ge) was created in single-crystalline Ge by ion implantation. It was shown that high optical density is available when implanting low-mass Al ions using a dual-energy approach. The optical properties were measured by multiple angle of incidence spectroscopic ellipsometry identifying the Cody-Lorentz dispersion model as the most suitable, that was capable of describing the dielectric function by a few parameters in the wavelength range from 210 to 1690 nm. The results of the optical measurements were consistent with the high material quality revealed by complementary Rutherford backscattering spectrometry and cross-sectional electron microscopy measurements, including the agreement of the layer thickness within experimental uncertainty

Investigation of the Tetrakis(dimethylamino)hafnium and H2S ALD Process: Effects of Deposition Temperature and Annealing

HfS2 has recently emerged as a promising 2D semiconductor, but the lack of a reliable method to produce continuous films on a large scale has hindered its spreading. The atomic layer deposition of the material with the precursor tetrakis-dimethylamino-hafnium with H2S is a rela- tively novel solution to this problem. This paper shows that it is a facile approach to synthesizing homogeneous and smooth HfS2 layers in a controlled and reproducible manner. The deposition is examined at different temperatures and layer thicknesses, exploring the ALD window of the deposition and the chemical, morphological and electronic properties of the films. The method yielded films with wafer-sized uniformity and controlled properties and is, thus, a promising way to prepare this important transition metal dichalcogenide material