AVS 53rd International Symposium
    Plasma Science and Technology Thursday Sessions
       Session PS-ThP

Paper PS-ThP2
Numerical Analysis of Oxygen Positive Column in Atmospheric Pressure Glow Discharge Plasmas

Thursday, November 16, 2006, 5:30 pm, Room 3rd Floor Lobby

Session: High Pressure Discharges and Novel Diagnostics & Sources Poster Session
Presenter: Y. Ichikawa, Fuji Electric Device Technology, Japan
Authors: Y. Ichikawa, Fuji Electric Device Technology, Japan
T. Suzawa, Fuji Electric Device Technology, Japan
M. Narita, Fuji Electric Device Technology, Japan
Correspondent: Click to Email
Recently, atmospheric pressure (AP) glow discharge plasmas have been studied by a number of researchers, because many applications are expected. The properties of AP plasmas, however, have not been understood very well yet. Thus, we have made an attempt to extend a positive column theory based on the ambipolar diffusion model to the AP range. Oxygen discharges have been widely used to various applications such as surface treatment for removal of organic materials, ashing, and ozonizing. For this reason, it is interesting to analysis oxygen AP positive column plasmas. Thus we carried out a numerical analysis of this discharge. In the simulation, we took into account four neutral species, O, O@sub 2@, O@sub 3@ and O@sub 2@(a@super 1@@DELTA@@sub g@), and eight ion species, O@super +@, O@sub 2@@super +@, O@sub 3@@super +@,O@sub 4@@super +@, O@super -@, O@sub 2@@super -@, O@sub 3@@super -@ and O@sub 4@@super -@. The transport equations for these charged and neutral species were solved simultaneously, and obtained the electron temperature and the abundance ratio of species self-consistently. The obtained results showed that the behavior of the plasma at the atmospheric pressure is quite different from that of the medium gas pressure range. The plasma density is higher than the electron density by more than an order of magnitude at higher gas pressures, and the major negative species is O@sub 3@@super -@ at the atmospheric pressure. For the positive ions, O@sub 4@@super +@ becomes the majority ion at around the atmospheric pressure. The obtained composition of neutral species showed that O@sub 3@ increases as the tube radius decreases at the atmospheric pressure.