Plasma chemical aspects

Morgan (1985), Manos and Flamm (1989), Liebermarm and Lichtenberg (1994), Roth (2001), and Chen and Chang (2003). In the following sections we focus on plasma-chemical aspects of etching technology, in particular applications for IC fabrication. 

Qualitatively, to model the chemically reacting plasma, neutral-species chemistry and transport and the electrical or plasma physics aspects of the discharge must be considered. The chemical and physical properties included in the model of the discharge must at least reflect the current understanding of the most important processes. The conventional view of discharge behavior has been described previously, but will now be reviewed briefly to set the stage for equation formulation. 

The material deposition that occurs in the low-pressure electrical discharge has been discussed under various terminologies such as plasma polymerization (PP), plasma-enhanced chemical vapor deposition (PECVD), plasma-assisted chemical vapor deposition (PACVD), plasma chemical vapor deposition (PCVD), and so forth [1]. However, none of these terminologies seems to represent the phenomenon adequately. The plasma aspect in the low-pressure discharge is remote, although it plays a key role in creating the environment from which material deposition occurs to the extent that no chemical reaction occurs without the plasma. In this sense, PECVD and PACVD could be out of the context in many cases in which nothing happens without plasma. In such cases, PP or PCVD would describe the phenomenon better. If the substrate was not heated substantially above the ambient temperature, the use of PECVD or PACVD should be avoided. 

Demnati, I., Grossin, D., Combes, C., and Rey, C. (2014) Plasma-sprayed apatite coatings review of physical-chemical aspects and their biological consequences. /. Med. Biol. Eng. 34 (1), 1-7. 

PRODUCTION OF HYDROGEN AND SULFUR TECHNOLOGICAL ASPECTS OF PLASMA-CHEMICAL HYDROGEN PRODUCTION... 

Technological Aspects of Plasma-Chemical Dissociation of Hydrogen Sulfide with Production of Hydrogen and Elemental Sulfur... 

Technological Aspects of H2 Production from Water in Double-Step and Multi-Step Plasma-Chemical Cycles... 

In the remainder of this chrqrter we describe recent trends in corona and low pressure plasma modification of polymer surfaces and interfaces, which we illustrate with results and examples fiom our own laboratories. Section 2 deals with a brief description of plasma-chemical principles and plasma-surface interactions, hr section 3, we describe how si ace modification can be characterized in terms of chemical structure, wettalnlity, etc., following which section 4 is devoted to adhesion of specific materials combinations, Ulustrated by case examples from these laboratories. In the concluding section, we comment on technological aspects and industrial scaleup. 

Alaupovic P (1986) Recent advances in metaboUsm of plasma Upoproteins chemical aspects. Prog Biochem Pharmacol 4 91-109... 

Rosenberg, S. A., and Einstein, A. B., Jr., 1972, Sialic acids on the plasma membrane of cultured human lymphoid cells. Chemical aspect and biosynthesis, J. Cell Biol. 53 466. 

Chemical vapor deposition is a synthesis process in which the chemical constituents react in the vapor phase near or on a heated substrate to form a solid deposit. The CVD technology combines several scientific and engineering disciplines including thermodynamics, plasma physics, kinetics, fluid dynamics, and of course chemistry. In this chapter, the fundamental aspects of these disciplines and their relationship will be examined as they relate to CVD. 

Further progress may derive from a more accurate definition of the chemical and physical properties of the humic substances present at the rhizosphere and how they interact with the root-cell apoplast and the plasma membrane. An interaction with the plasma membrane H -ATPase has already been observed however this master enzyme may not be the sole molecular target of humic compounds. Both lipids and proteins (e.g., carriers) could be involved in the regulation of ion uptake. It therefore seems necessary to investigate the action of humic compounds with molecular approaches in order to understand the regulatory aspects of the process and therefore estimate the importance of these molecules as modulators of the root-soil interaction. 

As already noted in Fig. 5.1, the ring opening of /3-lactam antibiotics is not only a major event in their interaction with bacterial enzymes, but occurs also in the mammalian body. Chemical hydrolysis in body fluids, metabolism by mammalian enzymes and interactions with plasma proteins, all influence the pharmacological activity of these antibiotics. These aspects will be considered below. We begin with the discussion of the chemical reactivity of the /3-lactam nucleus, which plays a key role in these events. 

The HMG-CoA reductase inhibitors therefore improve several aspects of the plasma lipid profile. These agents may produce several favorable effects that are independent of their ability to affect plasma lipid levels.9,96 It appears that certain by-products of cholesterol metabolism act directly or influence the production of other chemical signals that adversely affect cellular function in various tissues.9 Increased production of these by-products could therefore influence a variety of pathological conditions. By controlling the production of these by-products, statins may produce a wide range of beneficial effects in addition to their ability to improve plasma lipids. 

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