Current controlled Plasma-on-a-chip for atmospheric plasma generation

摘要

We present a plasma-on-a-chip operated in a current controlled bias scheme for atmospheric plasma generation. The plasma-on-a-chip was fabricated using micromachining techniques and includes an array of vertically formed micro gaps between an anode and a cathode, ranging from 5 um to 10 um. Use of a few micron gap enables atmospheric plasma generation at a relatively low voltage (～250 V). To enhance stability of the glow discharge, a current controlled bias scheme is suggested using a current mirror circuit. Compared to voltage controlled bias scheme, the current controlled scheme may improve stability of the glow discharge by suppressing excessive current flow occurred during the glow discharge, which may be caused by electrode-sputtering induced gap narrowing or elevated temperature. Electron and gas temperatures of the generated atmospheric plasma were measured to be 2550 K and 1000 K, respectively.