The characteristics of a stable discharge at atmospheric pressure is investigated.The plasma source consisted of two closely spaced parallel-plated perforated electrodes, driven by a radio frequency power to generate a uniform cold plasma in Helium at atmospheric pressure. Both alpha and gamma modes were clearly observed. The hollow cathode effects were found in the discharge. The influence of the dielectric barrier on the discharge was also investigated by utilizing a surface-anodized aluminium electrode as the anode.

The configuration and mechanism of a microhollow cathode discharge (MHCD) is introduced in this paper. The focus is a new type of cold atmospheric large-area plasma source, the fused hollow cathode (FHC) plasma source based on radio frequency hollow cathodes. Through its applications and related research, we present the characteristics of the hollow cathode discharge and the factors on which its characteristics depend, such as the cathode material, gas specy, frequency, gas flow, pressure, inner diameter of cathode, and the like. Two other types of related MHCD systems are given in addition.