Enhanced etch and deposition profile control using plasma sheath engineering

摘要

A plasma processing tool is used to deposit material on a workpiece. For example, a method for conformal deposition of material is disclosed. In this embodiment, the plasma sheath shape is modified to allow material to impact the workpiece at a range of incident angles. By varying this range of incident angles over time, a variety of different features can be deposited onto. In another embodiment, a plasma processing tool is used to etch a workpiece. In this embodiment, the plasma sheath shape is altered to allow ions to impact the workpiece at a range of incident angles. By varying this range of incident angles over time, a variety of differently shaped features can be created.

主权项

1. A method of etching a three dimensional feature, having a desired width, depth and taper, in a workpiece, comprising:
generating a plasma having a plasma sheath adjacent to a front surface of the workpiece; and modifying a shape of a boundary between the plasma and the plasma sheath while accelerating material from the plasma across the boundary to etch the three dimensional feature on the front surface of the workpiece wherein the material strikes the three dimensional feature at a range of incident angles, and wherein the range of incident angles is dependent on the shape of the boundary between the plasma and the plasma sheath.