Innovative electrochemical deep etching technique involving aluminum thermomigration

Sébastien Kouassi (1) , Gaël Gautier (2) , Laurent Ventura (2) , Chantal Boulmer-Leborgne (1) , Bernard Morillon , Mathieu Roy

1 GREMI - Groupe de recherches sur l'énergétique des milieux ionisés
2 GREMAN - UMR 7347 - GREMAN (matériaux, microélectronique, acoustique et nanotechnologies)

A novel micro-machining technique for silicon deep anisotropic etching and isolating porous siliconstructure formationis developped in this paper. This method combines aluminum thermomigration through a N type silicon wafer and silicon electrochemicaletching in a HF-based solution.Using this technique, high aspect ratio trenches (1:5) and porous silicopn isolating regions have been achievedthrough the entire thickness of the silicon wafers. Each rate measurements have been performed varying the anodization current density. A maximum value of 22µm/mn has been obtained. Moreover the porosity behavior with the current density increase is also discussed.

Domaines: Electronique

Sébastien Kouassi, Gaël Gautier, Laurent Ventura, Chantal Boulmer-Leborgne, Bernard Morillon, et al.. Innovative electrochemical deep etching technique involving aluminum thermomigration. physica status solidi (c), 2007, 4 (6), pp.2175. ⟨hal-00256833⟩