Erosion of the surface of electrodes in pulsed plasma evaporator

Abstract

In preparing thin films by concentration of a high speed plasma jet onto different substrates and also surface coating technology, many interesting physical problems may arise. We discussed the mechanism by which some evaporated dielectric or semiconductor material fall upon a substrate and estimate the rate of erosion of different evaporating electrode materials (Cu, Mo, C, ...). Dusty plasma jet of relatively high speed (10⁵ ∨ 10⁶ cm/s) is produced by a pulsed evaporating system. The measured erosion rate is compared with e phenomenologically calculated mass deposition on the substrate. In such plasmas with electron currents (10∨20kA), the following empirical relation has been found between mass erosion and discharge current:

$$\Delta m = KI^3 \tau ^2 ,$$

whereK is coefficient dependent on the thermal properties of the material and π is duration of an individual pulse.