Fluorocarbon polymer layer deposition predominant pre-etch plasma etch method for forming patterned silicon containing dielectric layer

摘要

A method for forming a patterned silicon containing dielectric layer within a microelectronics fabrication. There is first provided a substrate employed within a microelectronics fabrication. There is then formed over the substrate a silicon containing dielectric layer. There is then formed upon the silicon containing dielectric layer a hard mask layer, where the hard mask layer leaves exposed a portion of the silicon containing dielectric layer. There is then etched partially through a first plasma etch method the silicon containing dielectric layer to form a partially etched silicon containing dielectric layer. The first plasma etch method employs a first etchant gas composition comprising a first fluorocarbon etchant gas which predominantly forms a fluoropolymer layer upon at least the hard mask layer. Finally, there is then etched through a second plasma etch method the partially etched silicon containing dielectric layer to form a patterned silicon containing dielectric layer. The second plasma etch method employs a second etchant gas composition comprising a second fluoro etchant gas which predominantly etches the partially etched silicon containing dielectric layer in forming the patterned silicon containing dielectric layer.