Magnesium plasma diagnostics by heated probe and characterization of the Mg thin films deposited by thermionic vacuum arc technology
Abstract
The aim of this paper is to report on magnesium plasma diagnostics and to investigate the properties of thin Mg films deposited on Si and glass substrates by using thermionic vacuum arc (TVA) technology. TVA is an original deposition method using a combination of anodic arc and powerful electron gun system (up to 600 W) for the growth of thin films from solid precursors under a vacuum of 10(-6)Torr.
Due to the comparatively high deposition rate as well as comparatively high plasma potential-around 0.5 kV-plasma diagnostics were carried out by a heated probe that prevents layer deposition on the probe surface. The estimated value of electron density was in the order of 1.0 x 10(16)m(-3) and the electron temperature varied between 4 x 10(4) and 1.2 x 10(5) K (corresponding to two different discharge conditions).
The thin Mg films were investigated using SEM images and TEM analyses provided with HR-TEM and SAED facilities. According to the SAED patterns the structure of the films can be indexed as two forms: hexagonal structure for Mg and cubic structure for MgO; the peak value of grain size distribution was 91.29 nm in diameter for Mg TVA/Si and 61.06 nm for Mg TVA/Gl.