摘要 |
A method in a plasma processing system for etching a feature through a dielectric layer of a dual damascene stack on a semiconductor substrate is disclosed. The method includes placing the substrate in a plasma processing chamber of the plasma processing system. The method further includes flowing an etchant gas mixture into the plasma processing chamber, the etchant gas mixture being configured to etch the dielectric layer. The method additionally includes striking a plasma from the etchant source gas. The method also includes etching the feature through the dielectric layer while applying a bias RF signal to the substrate, the bias RF signal having a bias RF frequency of between about 27 MHz and about 90 MHz. The bias RF signal further has a bias RF power component that is configured to cause the feature to be etched in accordance to predefined etch rate parameters and etch profile parameters at the bias RF frequency.
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