Carbon-doped-Si oxide etch using H2 additive in fluorocarbon etch chemistry

摘要

Certain embodiments include an etching method including providing an etch material, applying a gas mixture including hydrogen, forming a plasma, and etching the etch material. The etch material can include a low-k dielectric material. The gas mixture can include a hydrogen gas, a hydrogen-free fluorocarbon, and a nitrogen gas, and further include one or more of a hydrofluorocarbon gas, an inert gas, and/or a carbon monoxide gas. The hydrogen gas can be a diatomic hydrogen, a hydrocarbon, a silane and/or a fluorine-free hydrogen gas, including H₂, CH₄, C₂H₄, NH₃, and/or H₂O gases. The hydrogen-free fluorocarbon gas can be a C_xF_y gas (where x>=1 and Y>=1) and the hydrofluorocarbon gas can be a C_xH_yF_z gas (where x>=1, y>=1 and z>=1). The gas mixture can be free of oxygen. Embodiments can include reduced pressures, reduced hydrogen flow rates and one or more plasma frequencies.