Determination of the relative concentration and the radial distribution of F radical atom concentration by plasma parameter normalization in ECR SF/sub 6//Ar discharge

摘要

Summary form only given, as follows. The relative concentration of the neutral radical atom can be determined by using optical emission actinometry (OEA). In OEA, a gas species called actinomer is added to compensate the effect of the plasma, that is, the excitation rate by electron impact. Therefore, if the concentration of the actinomer atoms can be assumed to be constant, the relative concentration of the radical atoms can be determined. But, for the nonuniform distribution of actinomer atom concentration which may appear in the fast pumping system (assumption of the constant radial profile of the actinomer concentration may not be proper). From this motivation, we have engaged an idea for the compensation of the plasma effect directly by using the plasma parameters which can be measured easily. We would call this as plasma parameter normalization method. Hutchinson derived a formula of k/sub c/ for the emission of atoms excited by the electrons of which energy distribution was Maxwellian. From this, we want to suggest a new method to determine relative concentration of the radical species, and the different change of the uniformities of the two neutral species, Ar, and F.