Electrical and ion beam analyses of Yttrium and Yttrium-Titanium getter thin films oxidation

Clément Bessouet (1) , Sylvain Lemettre (1) , Charlotte Kutyla (1) , Alain Bosseboeuf (1) , Philippe Coste (1) , Thierry Sauvage (2) , Hélène Lecoq (2) , Olivier Wendling (2) , Aurélien Bellamy (2) , Piyush Jagtap (3) , Stéphanie Escoubas (3) , Christophe Guichet (3) , Olivier Thomas (3) , Johan Moulin (1)

1 C2N - Centre de Nanosciences et de Nanotechnologies
2 CEMHTI - Conditions Extrêmes et Matériaux : Haute Température et Irradiation
3 IM2NP - Institut des Matériaux, de Microélectronique et des Nanosciences de Provence

Yttrium, Titanium and Yttrium-Titanium getter thin films were elaborated on silicon by co-evaporation in ultra-high vacuum. Y-Ti films exhibit nanometric crystallites size (18-35 nm) leading to a very high grain boundary density, which is a favorable microstructure for an activation at low temperature. The yttrium content in Y-Ti alloys influences grain size, resistance against room temperature oxidation and gettering performance for oxygen. Y-Ti films with an yttrium content higher than 30 % show strong oxygen sorption during annealing at low temperature (< 300 °C). After 1 h of annealing at 250 °C, it was estimated that the yttrium-based getter films can trap between 0.2 and 0.5 µmol of oxygen per cm 2 , while no oxygen sorption was detected for a single metal titanium film. This make Y-Ti getter alloys attractive candidates for the packaging of MEMS under vacuum with a low bonding temperature.

Mots clés: Yttrium alloys; oxidation; getter; thin films; low-temperature bonding; MEMS packaging

Domaines: Sciences de l'ingénieur [physics]

Clément Bessouet, Sylvain Lemettre, Charlotte Kutyla, Alain Bosseboeuf, Philippe Coste, et al.. Electrical and ion beam analyses of Yttrium and Yttrium-Titanium getter thin films oxidation. Journal of Vacuum Science & Technology A, 2021, 39 (5), pp.054202. ⟨10.1116/6.0001084⟩. ⟨hal-03398744⟩