SIMILARITIES IN SPATIAL DISTRIBUTIONS OF ABSOLUTE GEH2 DENSITY, RADICAL PRODUCTION-RATE AND PARTICLE AMOUNT IN GEH4 RF DISCHARGES

In order to study the particle growth processes in GeH4 RF discharges, the spatial distribution of the absolute GeH2 density is measured for the first time together with those of particle amount and radical pro duction rate (Ge emission intensity) in a moderately high power range of 0.5-1.0 W/cm(2). The particles are generated and grow around the pl asma/sheath boundary near the powered electrode, and the spatial distr ibution of their amount is similar to those of radical production rate and GeH2 density. Furthermore, GeH2 density is about 10(10) cm(-3), b eing close to SiH2 density in SiH4 discharges for the similar conditio ns of RF power and pressure. These results indicate that GeH2 is a hig hly reactive radical having a high production rate and hence is a cand idate for the main contributor to the particle growth.