Glow discharges properties

Key Words —Buckytubes, buckybundle, glow discharge, magnetic properties, transport properties. 

In this article, we describe and summarize our studies on the structural, magnetic,and transport properties of buckytubes. In addition, we describe how a conventional arc discharge can be modified into a stable glow discharge for the efficient synthesis of well-aligned buckytubes. 

The fugitive species SO was first identified by its ultraviolet spectrum in 1929 but it is thermodynamically unstable and decomposes completely in the gas phase in less than I s. It is formed by reduction of SOn with sulfur vapour in a glow discharge and its spectroscopic properties... 

In the early 1970s, Spear and coworkers (Spear, 1974 Le Comber et al., 1974), although unaware of the presence of hydrogen, demonstrated a substantial reduction in the density of gap states (with a corresponding improvement in the electronic transport properties) in amorphous silicon films that were deposited from the decomposition of silane (SiH4) in an rf glow discharge. 

Glow discharge or "cold" plasmas are gaining increased currency for the deposition of novel and potentially valuable macromolecular coatings. The range of properties attainable by a plasma-polymer is wide, and depends critically on such variables of the plasma deposition process as choice of monomer, substrate temperature (T ), power density (p), the excitation frequency (v), and others incluSing monomer flow rate, reactor geometry, etc... Control over these variables can produce crossllnked, dense deposits which adhere tenaciously to... 

Q. What property must the sample possess in order to be amenable to analysis by DC glow discharge spectrometry ... 

Plasma polymers are deposited on surfaces in contact with a glow discharge of organic or organometallic monomers, in the form of a thin film and/or as a powder. Such films find applications as surface modifiers and in applications where the bulk properties of extremely thin films are desirable. 

When alkylsilanes such as methylsilane, dimethylsilane, trimethylsilane, tetra-methylsilane, and hexamethyldisilane polymerize in a glow discharge, the stoichiometry, chemical structure, and properties of the resulting polymers generally depend on the discharge conditions (2, 8, 21, 22], Elemental compositions from XPS for plasma trimethylsilane polymers deposited under different... 

Table I. Properties of rf Glow Discharges (Plasmas) Used for Thin-Film Etching and Deposition...

Glow discharges or plasmas have been used extensively to promote chemical reactions for thin-film etching and deposition in a variety of technologically important areas. The reactive chemical atmosphere and complex discharge-surface interactions in these systems permit the attainment of unique etch profiles and film properties. 

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