USE OF ION BEAM ETCHING TO GENERATE GATE-ALL-AROUND STRUCTURE

摘要

Various embodiments herein relate to methods and apparatus for performing anisotropic ion beam etching to form arrays of channels. The channels may be formed in semiconductor material, and may be used in a gate-all-around device. Generally speaking, a patterned mask layer is provided over a layer of semiconductor material. Ions are directed toward the substrate while the substrate is positioned in two particular orientations with respect to the ion trajectory. The substrate switches between these orientations such that ions impinge upon the substrate from two opposite angles. The patterned mask layer shadows/protects the underlying semiconductor material such that the channels are formed in intersecting shadowed regions.

主权项

1. A method of forming channels or nanowires for a gate-all-around device or other electronic device, the method comprising:
(a) providing a substrate on a substrate holder in a reaction chamber, the substrate comprising a patterned mask layer over semiconductor material, wherein the patterned mask layer comprises a plurality of linear mask portions oriented substantially parallel to one another; (b) orienting the substrate with respect to an ion trajectory in a first orientation and directing ions toward the substrate in a first direction, wherein the ions impact the substrate at a first incidence angle to thereby anisotropically etch the semiconductor material to form a first set of trenches; (c) orienting the substrate with respect to the ion trajectory in a second orientation and directing ions toward the substrate in a second direction, wherein the ions impact the substrate at a second incidence angle to thereby anisotropically etch the semiconductor material to form a second set of trenches; (d) repeating (b)-(c) to further etch the first and second sets of trenches to form the channels or nanowires in a direction parallel to the plurality of linear mask portions.