Plasma gaseous products from

GASEOUS PRODUCTS FROM PLASMA ETCHING OF POP FILM ... 

Chemical vapor deposition includes various systems, and they are low-pressure CVD (LPCVD), atmospheric pressure CVD (APCVD), plasma enhanced CVD (PECVD), and others. Each type of CVD system has its own advantages and limitations. For instance, in LPCVD, the reactor is usually operated at 1 torr. Under this condition, the diffusivity of the gaseous species increases significantly compared to that under atmospheric pressure. Consequently, this increase in transport of the gaseous species to the reaction sites and the by-products from the reaction sites in LPCVD will not become the rate-limiting steps. This leads to the surface reaction step to be the rate limiting one. 

A scheme for bicyclic dimer formation from HMCTSN under plasma conditions has been proposed in our previous paper (J.) According to this scheme, formation of new Si-N bonds with tertiary nitrogen between trisilazane rings leads to crosslinking of the polymer, and involves the production of hydrocarbons such as methane and ethane. Indeed, gas chromatographic analysis of the gaseous residue after plasma polymerization has shown that it consists mainly of three hydrocarbons methane, ethane and ethylene in the 5 33 4 ratio. 

Fig. 7. Distribution of gaseous products as a function of rf power in a n-octane plasma. (Redrawn from Venugopalan, M., Hsu, P, Y.-W. Z. physik. Chem. Neue Folge, 102, 127 (1976), by permission of the authors and the publishers, Akademische Verlagsgesellschaft)...

Harkness, J.B.L., Fridman, A. (1999), The Technical and Economic Feasibility ofUsing Low-Temperature Plasmas to Treat Gaseous Emissions from Pulp Mills and Wood Product Plants, National Council of the Paper Industry for Air and Stream Improvement, NCASI, Research Triangle Park, NC. 

The normal and easiest way to produce plasma in any ion source is to use a gas dosing valve and inject the required element in gas form into the discharge chamber. Many elements of the periodic table, however, are not available in gaseous form. There have been various methods developed for ion production from solids. Some methods resulted in new types of ion sources... 

---