US Patent 10504738 Focus ring for plasma etcher

A method includes mounting a wafer on a chuck disposed within a chamber of an etching system, the wafer being encircled by a focus ring. While etching portions of the wafer, an etch direction is adjusted to a first desired etch direction by adjusting a vertical position of the focus ring relative to the wafer to a first desired vertical position. While etching portions of the wafer, the etch direction is adjusted to a second desired etch direction by adjusting the vertical position of the focus ring relative to the wafer to a second desired vertical position. The second desired vertical position is different from the first desired vertical position. The second desired etch direction is different from the first desired etch direction.