DOUBLE SELF-ALIGNED VIA PATTERNING

摘要

A method including forming a penta-layer hardmask above a substrate, the penta-layer hardmask comprising a first hardmask layer above a second hardmask layer; forming a trench pattern in the first hardmask layer; transferring a first via bar pattern from a first photo-resist layer above the penta-layer hardmask into the second hardmask layer resulting in a first via pattern, the first via pattern in the second hardmask layer overlapping the trench pattern and being self-aligned on two sides by the trench pattern in the first hardmask layer; and transferring the first via pattern from the second hardmask layer into the substrate resulting in a self-aligned via opening, the self-aligned via opening being self-aligned on all sides by the first via pattern in the second hardmask layer.

主权项

1. A method comprising:
forming a penta-layer hardmask above a substrate, the penta-layer hardmask comprising a first hardmask layer above a second hardmask layer; forming a trench pattern in the first hardmask layer; transferring a first via bar pattern from a first photo-resist layer above the penta-layer hardmask into the second hardmask layer resulting in a first via pattern, the first via pattern in the second hardmask layer overlapping the trench pattern and being self-aligned on two sides by the trench pattern in the first hardmask layer; transferring a second via bar pattern from a second photo-resist layer above the penta-layer hardmask into the second hardmask layer resulting in a second via pattern, the second via pattern in the second hardmask layer overlapping the trench pattern and being self-aligned on two sides by the trench pattern in the first hardmask layer; and transferring the first via pattern and the second via pattern from the second hardmask layer into the substrate resulting in a self-aligned via opening, the self-aligned via opening being self-aligned on all sides by the first via pattern in the second hardmask layer.