Applied Materials, Inc.
Controlling etch angles by substrate rotation in angled etch tools

Abstract:

Embodiments described herein relate to methods of forming gratings with different slant angles on a substrate and forming gratings with different slant angles on successive substrates using angled etch systems. The methods include positioning portions of substrates retained on a platen in a path of an ion beam. The substrates have a grating material disposed thereon. The ion beam is configured to contact the grating material at an ion beam angle .theta. relative to a surface normal of the substrates and form gratings in the grating material. The substrates are rotated about an axis of the platen resulting in rotation angles .PHI. between the ion beam and a surface normal of the gratings. The gratings have slant angles .theta.' relative to the surface normal of the substrates. The rotation angles .PHI. selected by an equation .PHI.=cos.sup.-1(tan(.theta.')/tan(.theta.)).