A microplasma discharge using a plasma reservoir source

Abstract

Summary form only given. A microplasma in a slit structure has been generated using an Inductively Coupled Plasma (ICP) source as a plasma reservoir. This unique configuration uses a slit structure fabricated in a Low Temperature Co-Fired Ceramic (LTCC) substrate. At the top of the substrate, a spiral ICP antenna [1] is fabricated 35 μm below the surface of the LTCC. This antenna is used to generate plasma above the substrate and over a slit that has been milled through the substrate at the center of the antenna spiral. The operating frequency is 800-1000 MHz with power levels from 0.5 to 50 W. Slits have been tested with diameters ranging from 0.4 to 1.2 mm. Embedded in the slits are two electrodes placed directly opposite each other. These electrodes are exposed to the slit vacuum space to act as electrodes for a DC glow discharge. When the ICP source is operated at pressures from 0.1 to 40 Torr in argon, a DC glow discharge can be initiated from the exposed electrodes. One of the electrodes is biased positive with respect to the antenna and the second electrode, both held at ground. This bias pulls electrons into the slit or channel and initiates the DC discharge between the two electrodes or between the electrode and the plasma reservoir. In this second case, the reservoir acts a virtual cathode. The goal of the project is to create transistor functionality by using an additional gate electrode. Experimental results of the device operation over a range of pressures and ICP powers will be presented. Simulation of the device structure using OOPIC will also be presented.