A low frequency impedance matching circuit for a one atmosphere uniform glow discharge plasma reactor

Abstract

Summary form only given. The OAUGDP reactor with plasma on can be modeled as two or three capacitors in parallel with a resistor. The non-ideality of the transformer between the RF power supply and the plasma reactor also has an imaginary part in its impedance. Thus, the whole load of the power supply, seen by its output terminals, is highly reactive. The impedance mismatch resulting from the absence of a matching network can cause a large reflected power from the load which does not contribute to plasma formation, but requires an expensive over-rated power supply. In addition, the reactive current can deposit charge on the surface of the dielectric which does not face the plasma. This will disturb the memory voltage and may complicate attempts to achieve a uniform (as opposed to filamentary) discharge. In this paper, we will present the design details of a new impedance matching circuit which matches the load at the primary side of the transformer. This arrangement avoids dealing with impedance matching components at high voltage in the secondary-side matching circuit presented in our last year's paper. Some new data and improvements of plasma reactor operation will also be presented.