Properties of dielectric-barrier-free atmospheric pressure microplasma driven by submicrosecond dc pulse voltage

Abstract

Atmospheric pressure microplasma driven by dc pulse is developed. This device has a simple structure comprised of a flowing helium (He) feed gas and dielectric-free metal electrodes without an external current limiting resistor. It is shown that a stable glow mode plasma can be sustained without arc runaway by limiting the voltage pulse width to shorter than 300 ns. The properties of the device are reported in terms of discharge current waveforms, rotational temperature of N2+, and spatiotemporally resolved optical emission characteristics.