STUDY ON INITIAL GROWTH OF PARTICLES IN LOW-PRESSURE AND LOW-POURER GEH4 RF DISCHARGES USING THE HIGH-SENSITIVITY PHOTON-COUNTING LASER-LIGHT-SCATTERING METHOD

Citation
H. Kawasaki et al., STUDY ON INITIAL GROWTH OF PARTICLES IN LOW-PRESSURE AND LOW-POURER GEH4 RF DISCHARGES USING THE HIGH-SENSITIVITY PHOTON-COUNTING LASER-LIGHT-SCATTERING METHOD, JPN J A P 2, 37(10B), 1998, pp. 1264-1267
Citations number
14
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics, Applied
Volume
37
Issue
10B
Year of publication
1998
Pages
1264 - 1267
Database
ISI
SICI code
0021-4922(1998)37:10B<1264:SOIGOP>2.0.ZU;2-P
Abstract
A high-sensitivity photon-counting laser-light-scattering method is ap plied to obtain information on initial growth of particles formed in l ow pressure and low power GeH4 RF discharges. Particles of about 1 nm in size are detected principally around the plasma/sheath boundary nea r the RF electrode at an early time of 0.2 s after the discharge initi ation and the corresponding particle density of 2 x 10(11) cm(-3) is a bout two orders of magnitude higher than ion density. Spatial profiles of particle amount are very similar to those of Ge emission intensity which indicates a radical production rate. These results suggest that short-lifetime radicals such as GeH2, having a high production rate, are candidates for key species contributing to the nucleation and init ial growth of particles, even for a low pressure (8-13 Pa) and a low p ower density (0.04 W/cm(2)). Furthermore, surface reflection probabili ties of particles 1-12 nm in size, measured after RF-power-off, are fo und to be more than 80%.