Working Principle of the Hollow-Anode Plasma Source

Publication Type

Journal Article

Date Published

11/1995

LBNL Report Number

LBL-36240

Abstract

The hollow-anode discharge is a special form of glow discharge. It is shown that a drastically reduced anode area is responsible for a positive anode voltage drop of 30-40 V and an increased anode sheath thickness. This leads to ignition of a relatively dense plasma in front of the anode hole. Langmuir probe measurements inside a specially designed hollow anode plasma source give an electron density and temperature of ne=109-1011 cm-3 and Te=1-3 eV, respectively (nitrogen, current 100 mA, flow rate 5-50 scc min-1). Driven by a pressure gradient, the 'anode' plasma is blown through the anode hole and forms a bright plasma jet streaming with supersonic velocity (Mach number 1.2). The plasma-stream can be used, for instance, in plasma-assisted deposition of thin films.

Journal

Plasma Source Science and Technology

Volume

4

Year of Publication

1995

Short Title

Plasma Sources Sci. Technol.

Issue

4
571

Pagination

571-575

Other Numbers

UC-426