Dust growth instabilities in silane-based plasmas

Marjorie Cavarroc (1) , Maxime Mikikian (1) , Yves Tessier (1) , Laifa Boufendi (1)

1 GREMI - Groupe de recherches sur l'énergétique des milieux ionisés

In this paper we report on two instabilities observed in dusty plasmas, at different stages of dust particle formation. Experiments are performed in a low-pressure Ar/SiH4 radiofrequency plasma. The first instability, occuring at the transition between nanocrystal accumulation and coalescence phases, is very sensitive to operating conditions. It is shown to be a good indicator of the end of nanocrystal accumulation phase in the plasma. This “coalescence instability” seems to be an attachment induced-ionization instability as observed in electronegative gases. The second instability starts during the second dust generation formation. It exhibits a complex scheme closely linked to dust successive generations. This instability is suspected to be a void instability. Indeed, the occurence of this “successive generation instability”, combined with laser light scattering and Ar*(750.38 nm) line spectroscopic measurements indicate a possible void region in the dust cloud, as observed in PKE experiments.

Mots clés: Void; Agglomeration; Dusty plasma; Complex plasma; Silane; Plasma; Instabilities; Generations; Nanocrystal; Nanoparticle

Domaines: Plasmas; Physique des plasmas [physics.plasm-ph]

Marjorie Cavarroc, Maxime Mikikian, Yves Tessier, Laifa Boufendi. Dust growth instabilities in silane-based plasmas. 15th Annual Student Conference, Week of Doctoral Students, Jun 2006, Prague, Czech Republic. pp.59. ⟨hal-00445231⟩