The Harmonic Distortion Factor of the Current of Radio‐Frequency Low‐Pressure Discharges

Abstract

AbstractIn order to characterize an r.f. low‐pressure discharge in diode systems which are capacitively coupled to the r.f. generator the content of harmonics in current and voltage is experimentally investigated. The discharge‐conditioned content of harmonics in the voltage is practically negligible. The spectrum of the discharge current is qualitatively and quantitatively dependent on the whole reactor/generator arrangement producing the discharge. For an asymmetrical diode with a self‐excited generator it is shown that the content of harmonics in the discharge current is highly dependent on the radio‐frequency voltage, the d.c. self‐bias of the r.f. electrode, the effective power and the pressure. Conclusions are discussed concerning a connection between the content of harmonics, on the one hand, and carrier‐density modulation and power dissipation at the substrate electrode, on the other hand.