Plasma technology process

Dielectric Film Deposition. Dielectric films are found in all VLSI circuits to provide insulation between conducting layers, as diffusion and ion implantation (qv) masks, for diffusion from doped oxides, to cap doped films to prevent outdiffusion, and for passivating devices as a measure of protection against external contamination, moisture, and scratches. Properties that define the nature and function of dielectric films are the dielectric constant, the process temperature, and specific fabrication characteristics such as step coverage, gap-filling capabihties, density stress, contamination, thickness uniformity, deposition rate, and moisture resistance (2). Several processes are used to deposit dielectric films including atmospheric pressure CVD (APCVD), low pressure CVD (LPCVD), or plasma-enhanced CVD (PECVD) (see Plasma technology). 

Microwaves may be used to ionize gases when sufficient power is apphed, but only through the intermediate process of classical acceleration of plasma electrons. The electrons must have energy values exceeding the ioniza tion potential of molecules in the gas (see Plasma technology). Ionizing radiation exhibits more biological-effect potential whatever the power flux levels (2). 

I. W. Boyd and E. E. Krimmel, eds.. Photo, Beam and Plasma Assisted Processing—Fundamentals and Device Technology, Elsevier Science, Inc., New York,... 

J. Eeinman, ed.. Plasma Technology in Metallurgical Processing, Books on Demand, Ann Arbor, Mich., 1986. 

Masuda, S. (1998) Pulse corona induced plasma chemical process a horizon of new plasma chemical technologies, Pure Appl. Chem. 60, 727-31. 

Partial oxidation is also mentioned as a process to convert ethanol to hydrogen.124 Another novel technology for ethanol to hydrogen has been described by Toci and Modica.125 It is based on cracking ethanol vapors by "cold-plasma-chemical processing" in the presence of a Ni-based catalyst. 

The implied capability of these plasma deposits to inhibit corrosion at metal surfaces may be of practical as well as of basic importance. An important consideration in this respect is the rapid rate of deposition for such protective coatings attainable at micro-wave frequencies. Since plasma technology is still in a process of evolution, optimum deposition kinetics cannot yet be stated however, the marked effect of excitation frequency on the deposition of organo-silicones can be documented (10), as in Fig. 3. Here, using terminology and comparative data due to Yasuda et al. (2). it is shown that deposition rates in microwave plasmas exceed those at lower (e.g. radio) frequencies by about an order of magnitude. 

T0696 Science Applications International Corporation, Plasma Hearth Process T0701 Seiler Pollution Control Systems, High-Temperature Vitrification System T0704 Selective Environmental Technologies, Inc., MAG SEP... 

The Environmental Dynamics low-temperature plasma (LTP) process is an ex situ technology that treats soils contaminated with volatile organic compounds (VOCs). According to the vendor, the technology has the following advantages ... 

Plasma technologies have traditionally been very expensive. In addition, research indicates that the PARCON technology may produce potentially toxic by-products when processing chemical agents or energetics (although the vendor claims these by-products are less hazardous than target contaminants and the amounts produced are fairly small). 

Plasmas can be classified as either thermal or non-thermal. " Thermal plasma is a highly energetic state of matter, characterized by thermal equilibrium between the three components of the plasma electrons, ions, and neutrals. However, it requires high-energy input to achieve high temperatures. Researchers at MIT used a non-catalytic thermal plasma technology to produce H2 from liquid hydrocarbons. Non-catalytic processes are beyond the scope of this work, and will not be discussed. 

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