Ryohei Itatani

Niihama National College of Technology
7-1 Yagumo-cho Niihama Ehime Japan
itatani@niihama-nct.ac.jp

The concept and methods to control reactive plasmas are discussed, and examples are demonstrated.

The role of plasmas is to decompose stable molecules into chemically active species and to transport them onto surfaces on which various useful reactions take place. There, the main role of reaction is played by electrons the energy of which is one of key parameters to characterize reactive plasmas. Ion flux from a plasma is a function of electron energy. Thus, control of electron energy is most important to control reaction in the reactive plasma for both flux of radical and ion.

A reactive plasma is described theoretically as a set of dynamic systems with both of the source and the loss term each of which is characterized with each own time constant evaluated with crosssection and basic parameters such as plasma dimension and gas pressure etc. The concept of time constants makes analysis of chemical reactions simple.

Examples to control plasmas by changing boundary condition artificially and by using difference of time constant of reaction are demonstrated.