Effects of annealing temperature (T a ) on the structure of hydrogenated amorphous silicon carbide (a-SiC:H) films prepared by RF plasma chemical vapor deposition (CVD) method are investigated by using Fourier Transform-Infrared Spectrometry (FT-IR), X-ray Photoelectron Spectroscopy (XPS) and UV-VIS spectrophotometer techniques. It is found that an annealing process results in structural rearrangement and evacuation of hydrogen atoms from CH n and SiH n bonds. The emission of hydrogen bonded to silicon and carbon responsible for the decrease of optical band gap (E opt ) by 0.70 eV in the range of T a from 573 to 873 K. This hydrogen loss is interpreted in terms of hydrogen molecule formation and outerdiffusion. In addition, the surface morphology of films was investigated by atomic force microscopy (AFM).
Plasma-polymer pure ethylcyclohexane thin lms were deposited on Si(100) substrates at room temperature by using PECVD (plasma enhanced chemical vapor deposition). Hydrogen and argon gases were used as precursor bubbler and carrier gases, respectively. We also investigated the electrical and the physical properties of the plasma-polymer thin lms at various deposition RF powers and annealing temperatures. The as-grown and the annealed plasma-polymer thin lms were analyzed by using FT-IR (Fourier transform infrared spectroscopy) and SEM (scanning electron microscopy). The IR spectra showed that the plasma-polymer thin lms had totally dierent chemical functionalities from those of the ethylcyclohexane precursor and that the chemical functionalities of the thin lms changed with the RF power and annealing temperature. From the SEM results, we determined the thicknesses of the thin lms before and after the annealing, with the thickness shrinkage (%) being measured by using SEM cross-sectional images. An impedance analyzer was used to measure the capacitance and from the electrical property measurements, the lowest dielectric constant obtained was 1.71.
The characteristics of a pulsed plasma jet originating from an electrothermal capillary discharge have been investigated using laser-induced fluorescence (LIF) measurement. Previous emission spectroscopic measurements of a 3.1 kJ plasma jet show that upstream of the Mach disk the temperature and electron number density are about 14,000 K and 10 11 em-a, while downstream of the Mach disk the values are about 25,000 K and 10 18 em-a, respectively. However, these values are based on line-of-sight integrated measurements that may be misleading. Hence, LIF is being used to provide both spatially and temporally resolved measurements. Our recent work has been directed at using planar laser-induced fluorescence (PLIF) imaging of atomic copper in the plasma jet flow field. Copper is a good candidate for PLIF studies because it is present throughout the plasma and has electronic transitions that provide an excellent pump-detect strategy. Our PLIF results to date show that emission measurements may give a misleading picture of the flow field, as there appears to be a large amount of relatively low temperature copper outside the barrel shock, which may lead to errors in temperature inferred from emission spectroscopy. In this paper, the copper LIF image is presented and at the moment, relative density of atomic copper, which is distributed in the upstream of the pulsed plasma jet, is discussed qualitatively.
To reveal the effects of compositional changes in the structure of potassium lithium niobate (K3Li,_~Nb,_~O,,) grown by the micro-pulling down (/.t-PD) method, the structure and polar atomic displacements of the metal atoms were studied by X-ray analysis. The polar components of the atomic displacement oft_he metal atoms Nb(1) and Nb(2) was determined to be 0.193 and 0.186 , 0.162 and 0.154, and 0.115 and 0.114 for melt compositions of x=-0.3, 0, and +0.3, respectively. It was shown that the displacements of the Nb sites increased as the Nb content decreased.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.