Measurement of plasma discharge characteristics for sputtering applications

Plasma and characteristics of rf and dc discharges for sputtering were measured by a cylindrical-type electrostatic probe. Space potentional, floating potential, electron temperature, and plasma density were monitored as a function of discharge voltage, substrate bias, and probe position within the chamber. A description of the probe and supporting circuit used to plot the current–voltage characteristic is given. The electrostatic probe was shown to be a useful tool for characterizing sputtering process and with suitable system calibration, can be used to enhance repeatability of the sputtering process.