Gas Rotational Temperature in an RF Plasma

Abstract

The molecular gas temperature in an rf glow discharge of was determined by analysis of the unresolved rotational structure of the emission spectrum. The emission spectrum was recorded for the rf discharge (13.56 MHz) in at a pressure of 1.0 Torr and an rf power of 1000W. Using a technique previously applied to pulse discharges in by Phillips (1), the unresolved 0'–3'' and 1'–4'' vibronic bands of the second positive system were analyzed. The least squares fit to these bands indicated a temperature of . This measurement of the molecular gas temperature is applicable to the type of rf plasmas used to process semiconductor materials.