Self aligned via and pillar cut for at least a self aligned double pitch
First Claim
1. A method of forming via openings comprising:
- forming a first set of spacers on sidewalls of a first set of mandrels, the first set of mandrels present on a mandrel material layer for forming a second mandrel that is present overlying a hardmask layer and at least one interlevel dielectric layer;
etching the mandrel material layer using the first set of spacers as an etch mask to form a second set of mandrels, wherein etching the mandrel material layer includes removing the first set of mandrels;
forming a second set of spacers on sidewalls of the second set of mandrels;
etching the hardmask layer using the second set of spacers and the second set of mandrels to define a first pillar of hardmask material;
etching the interlevel dielectric layer using the first pillar of hardmask material and a first via etch mask to provide a first via opening;
removing the second set of mandrels; and
forming a second via opening in the interlevel dielectric layer.
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Accused Products
Abstract
A method of forming via openings that includes forming sidewall spacers on a plurality of mandrels that are overlying a hardmask layer that is present on an interlevel dielectric layer. Etching the hardmask layer using a portion of the sidewall spacers and the plurality of mandrels to form a first pillar of hardmask material. The interlevel dielectric layer is etched using the first pillar of hardmask material as a mask to define a first via opening. The plurality of mandrels are removed. The hardmask layer is etched using the spacers to define a second pillar of hardmask material. The interlevel dielectric layer is etched using the second pillar of hardmask material to provide a second via opening.
6 Citations
8 Claims
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1. A method of forming via openings comprising:
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forming a first set of spacers on sidewalls of a first set of mandrels, the first set of mandrels present on a mandrel material layer for forming a second mandrel that is present overlying a hardmask layer and at least one interlevel dielectric layer; etching the mandrel material layer using the first set of spacers as an etch mask to form a second set of mandrels, wherein etching the mandrel material layer includes removing the first set of mandrels; forming a second set of spacers on sidewalls of the second set of mandrels; etching the hardmask layer using the second set of spacers and the second set of mandrels to define a first pillar of hardmask material; etching the interlevel dielectric layer using the first pillar of hardmask material and a first via etch mask to provide a first via opening; removing the second set of mandrels; and forming a second via opening in the interlevel dielectric layer. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
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Specification