摘要 |
A method for etching features into an etch layer in a plasma processing chamber, comprising a plurality of cycles is provided. Each cycle comprises a deposition phase and an etching phase. The deposition phase comprises providing a flow of deposition gas, forming a plasma from the deposition gas in the plasma processing chamber, providing a first bias during the deposition phase to provide an anisotropic deposition, and stopping the flow of the deposition gas into the plasma processing chamber. The etching phase, comprises providing a flow of an etch gas, forming a plasma from the etch gas in the plasma processing chamber, providing a second bias during the etch phase, wherein the first bias is greater than the second bias, and stopping the flow of the etch gas into the plasma processing chamber. |