Inductively coupled plasma etching of ultra-shallow Si3N4 nanostructures using SF6/C4F8 chemistry

Bruno Lee Sang (1, 2) , Marie-Josée Gour (1, 2) , Abdelatif Jaouad (1, 2) , Serge Ecoffey (1, 2) , Maxime Darnon (1, 2, 3) , Benattou Sadani (1, 2) , Abdelkader Souifi (4, 1, 2) , Dominique A Drouin (1, 2)

1 LN2 - Laboratoire Nanotechnologies Nanosystèmes
2 3IT - Institut Interdisciplinaire d'Innovation Technologique [Sherbrooke]
3 LTM - Laboratoire des technologies de la microélectronique
4 INL - DE - INL - Dispositifs Electroniques

A reproducible inductively coupled plasma (ICP) etching process using simultaneously SF 6 /C 4 F 8 gases for the fabrication of ultra-shallow Si 3 N 4 nanostructures is presented. The effect of varying etching parameters such as the coil and platen RF power, the chamber pressure, the C 4 F 8 flow rate and the platen temperature on Si 3 N 4 and ZEP etch rates are investigated. The passivation and etching chemistry balance is used to slow down the Si 3 N 4 etch rate to a limit of 6 nm/min. For lower etch rates, the passivation regime is getting dominant and the surface roughness increases. 10 nm deep Si 3 N 4 nanostructures are patterned without inducing any additional roughness on etched surfaces.

Domaines: Micro et nanotechnologies/Microélectronique

Bruno Lee Sang, Marie-Josée Gour, Abdelatif Jaouad, Serge Ecoffey, Maxime Darnon, et al.. Inductively coupled plasma etching of ultra-shallow Si3N4 nanostructures using SF6/C4F8 chemistry. Microelectronic Engineering, 2015, 141, pp.68 - 71. ⟨10.1016/j.mee.2015.01.014⟩. ⟨hal-01916788⟩