New Method to Measure the Electron Temperature and the Plasma Density in a Single-Frequency Capacitive Discharge

A new method to determine electron temperatures and plasma densities by measuring the floating potential, the substrate potential, and the current flowing through a substrate in single-frequency capacitive discharges is proposed. We equated the electron temperature with the floating and the substrate potentials by using a flux balance equation, and from this, the electron temperature could be determined from the measured maxima of the floating and the substrate potentials. The ion saturation current could also be extracted from the measured substrate current. When the substrate potential reached its maximum, the displacement current flow through the substrate became zero, and we could determine the ion saturation current and the plasma density.