Method of manufacturing a structure by asymmetrical ion bombardment of a capped underlying layer

A method of patterning a semiconductor structure comprising:

• forming a layer stack above a semiconductor substrate, comprising:
• forming an underlying layer, wherein the underlying layer is an amorphous layer or a polycrystalline layer;
• and
• forming a capping layer on the underlying layer;
• and
• asymmetrically modifying the underlying layer, comprising:
• etching the layer stack to form a plurality of features in a first pattern, each feature having opposite first and second underlying layer sidewalls, wherein:
• the features in the first pattern have a first pitch and a first spacing in a first direction parallel to a surface of the semiconductor substrate;
• and
• each feature has a vertical axis of symmetry orthogonal to the semiconductor substrate;
• and
• directing ions at a non-orthogonal angle with respect to the surface of the semiconductor substrate, wherein:
• the directed ions bombard the first underlying layer sidewalls;
• and
• the second underlying layer sidewalls are protected from ion bombardment by the capping layer, such that unbombarded portions of the underlying layer form sub-features in a second pattern, wherein:
• the sub-features in the second pattern have the first pitch and a second spacing in the first direction greater than the first spacing;
• each sub-feature has a vertical axis of symmetry orthogonal to the semiconductor substrate;
• and
• the vertical axes of symmetry of the sub-features are laterally shifted from the vertical axes of symmetry of the features.

A method comprising:

• forming a layer stack above a semiconductor substrate, comprising:
• forming a dielectric layer;
• forming an underlying layer on the dielectric layer;
• and
• forming a capping layer on the underlying layer;
• forming a photoresist on the layer stack;
• forming a pattern in the photoresist;
• transferring the pattern in the photoresist to the capping layer and to the underlying layer to expose sidewalls of the underlying layer;
• and
• asymmetrically bombarding portions of the underlying layer, comprising:
• directing ions at a non-orthogonal angle with respect to a surface of the semiconductor substrate, wherein:
• the directed ions bombard a first portion of the sidewalls of the underlying layer along a vertical length extending between the capping layer and the dielectric layer;
• and
• a second portion of the sidewalls of the underlying layer is protected from ion bombardment by the capping layer.

A method comprising:

• forming a layer stack above a semiconductor substrate, comprising:
• forming an underlying layer, wherein the underlying layer is a temporary layer that does not remain in a finished integrated circuit;
• and
• forming a capping layer on the underlying layer;
• forming a photoresist on the layer stack;
• forming a pattern in the photoresist;
• transferring the pattern in the photoresist to the capping layer and to the underlying layer to expose sidewalls of the underlying layer;
• and
• asymmetrically bombarding portions of the underlying layer, comprising:
• directing ions at a non-orthogonal angle with respect to a surface of the semiconductor substrate, wherein:
• the directed ions bombard a first portion of the sidewalls of the underlying layer;
• and
• a second portion of the sidewalls of the underlying layer is protected from ion bombardment by the capping layer.