Development of porosimetry techniques for the characterization of plasma-treated porous ultra low-K materials

Christophe Licitra (1) , Thierry Chevolleau (2) , Régis Bouyssou (2) , Mohamed El Kodadi (2) , Georg Haberfehlner (1) , Jérôme Hazart (1) , Leopold Virot (1) , Maxime Besacier (2) , Nicolas Possémé (1) , Maxime Darnon (2) , R. Hurand (2) , P. Schiavone (2) , F. Bertin (1)

1 CEA-LETI - Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information
2 LTM - Laboratoire des technologies de la microélectronique

For the sub-32 nm node, porous SiCOH dielectrics (p-SiCOH) are integrated using dual damascene patterning by etching trenches and vias into the porous material. One challenge is to control the process conditions to minimize the plasma-induced damage of p-SiCOH materials at the bottom and at the sidewall of the trenches. Ellipsometric Porosimetry has been adapted to characterize the plasma-treated materials for both horizontal and vertical surfaces. Since surface modifications can cause adsorption and desorption delays and hydrophobicity loss, porosimetry measurements operated with multi-solvent and kinetic protocols are required. Quantitative measurements of vertically patterned materials are demonstrated using periodic structures of porous material and a Scatterometric Porosimetry analysis. Results show a good sensitivity of the measurement to the different process conditions but also highlight a different impact of the plasma processes on patterned materials compared with blanket films.

Domaines: Micro et nanotechnologies/Microélectronique

Christophe Licitra, Thierry Chevolleau, Régis Bouyssou, Mohamed El Kodadi, Georg Haberfehlner, et al.. Development of porosimetry techniques for the characterization of plasma-treated porous ultra low-K materials. ECS Transactions, 2011, 35 (4), pp.729-746. ⟨10.1149/1.3572316⟩. ⟨hal-00625361⟩