CONTRIBUTION OF SHORT LIFETIME RADICALS TO THE GROWTH OF PARTICLES INSIH4 HIGH-FREQUENCY DISCHARGES AND THE EFFECTS OF PARTICLES ON DEPOSITED FILMS

Particle growth processes and the contribution of shea lifetime radica ls to the processes in SiH4 high frequency plasmas for a moderately hi gh power above 0.25 W/cm(2) are studied using polarization-sensitive l aser light scattering, a newly developed Langmuir probe, a novel photo detachment, transmission electron microscopy, atomic force microscopy, and intracavity laser absorption methods together with a discharge mo dulation method. Particles are generated and grow from their nucleatio n phase principally around the plasma/sheath boundary near the powered electrode. Spatial profiles of the particle amount are very similar t o those of production rates and densities of short lifetime radicals. The SiH2 density is low in spite of its high production rate. While th e SiH2 density in the early discharge stage for 28 MHz is about one or der higher than that for 6.5 MHz, the particle density for 28 MHz is t wo orders higher than that for 6.5 MHz. These results suggest that sho rt lifetime radicals, in particular SiH2 radicals, not only participat e mainly in the particle nucleation but also contribute numerous times to the nucleation and subsequent initial growth reactions of one part icle. Moreover, photodetachment measurements showed that clusterlike p articles exist even in the bulk plasma; some of them are considered to be neutral and hence they are likely to be transported to the substra te on the grounded electrode. (C) 1996 American Vacuum Society.