Patent ID: 8691698
Filing Date: 2014-04-08
Classification: H01L

Abstract:
1. A method for etching features in a silicon layer disposed below a mask in a plasma processing chamber, comprising a plurality of cycles, wherein each cycle comprises: providing a deposition phase forming a deposition on the silicon layer in the plasma processing chamber, comprising; providing a deposition gas into the plasma processing chamber wherein the deposition gas comprises a halogen containing etchant component and a fluorocarbon deposition component; forming the deposition gas into a plasma, which provides a net deposition on the silicon layer; and stopping the flow of the deposition gas; and providing a silicon etch phase, comprising; providing a silicon etch gas into the plasma processing chamber that is different than the deposition gas; forming the silicon etch gas into a plasma to etch the silicon layer; and stopping the flow of the silicon etch gas.