Method of etching a porous dielectric material

US10062602B2 · kind B2 · utility

Assignees

• COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES · FR
• CNRS-CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE · FR
• Applied Materials, Inc. · US

Inventors

• Nicolas Posseme · Grenoble, FR
• Sebastien Barnola · Meylan, FR
• Olivier Joubert · Meylan, FR
• Srinivas D. Nemani · Sunnyvale, US
• Laurent Vallier · Montbonnot-Saint-Martin, FR

Key dates

• Filing date: Dec 27, 2013
• Grant date: Aug 28, 2018
• Expiry date: Nov 2, 2034

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L2221/1063
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

The invention relates to a method of etching a layer of porous dielectric material, characterized in that the etching is performed in a plasma formed from at least one silicon-based gas mixed with oxygen (O2) and/or nitrogen (N2) so as to grow a passivation layer all along said etching, at least on flanks of the layer of porous dielectric material and wherein the silicon-based gas is taken from all the compounds of the type SixHy for which the ratio x/y is equal or greater than 0.3 or is taken from all the compounds of the following types: SixFy and SixCly, where x is the proportion of silicon (Si) in the gas and y is the proportion of fluorine (F) or chlorine (Cl) or hydrogen (H) in the gas.