Characteristics of low pressure sulfur discharges

Abstract

Summary form only given, as follows. Sulfur (S) and S-Ar discharges have been studied over a wide range of operating conditions. Both DC positive column discharges and inductively coupled 13.56 MHz discharges have been studied. Even though the partial pressure of S/sub 2/ is low in the 50 C-200 C temperature range investigated here, the primary radiating molecule in these discharges is S/sub 2/. The majority of the spectral emission occurs in the 2800 /spl Aring/-3500 /spl Aring/ range. The spectrum observed from the 13.56 MHz discharge corresponds nicely to that obtained from DC discharges at much higher temperatures. The radiation output has been studied as a function of input power, discharge temperature, buffer gas pressure, discharge radius, and cold spot temperature. The absolute efficiency of the discharge in generating near ultraviolet radiation has been investigated and results are presented for many areas of the multidimensional parameter space.