Time-resolved layer thickness behavior of microcrystalline and amorphous silicon samples after switching on a hydrogen/silane VHF plasma

In the course of deposition and etch experiments - (a) on blank borosilicate glass substrates, (b) on borosilicate glass substrates coated with thin amorphous or microcrystalline films ('precoated substrates'), (c) 'layer-by-layer (Lbl) experiments' - the film thickness was measured in situ. Varying seeding' times - up to ∼ 2000 s for (SiH 4 /(SiH 4 + H 2 )) = 1.5% and substrate temperature T S = 180 °C on the blank substrates were detected, before a continuous growth started. Using the Lbl technique, high crystalline silicon layers (up to 70% Raman crystallinity) were reached. The experimental results will be compared with results of a simple 3D-simulation of the μc-Si growth process and will be discussed in context with the favored growth models for microcrystalline silicon ('diffusion model', 'etching model', growth zone model').