Method for creating self-aligned transistor contacts

摘要

Embodiments of the present invention provide improved methods of contact formation. A self aligned contact scheme with reduced lithography requirements is disclosed. This reduces the risk of shorts between source/drains and gates, while providing improved circuit density. Cavities are formed adjacent to the gates, and a fill metal is deposited in the cavities to form contact strips. A patterning mask is then used to form smaller contacts by performing a partial metal recess of the contact strips.

主权项

1. A method of forming a semiconductor structure, comprising:
forming a plurality of gates in a dielectric layer; recessing the plurality of gates; depositing a capping layer over the plurality of gates; forming a first mask layer having a patterned opening therein; performing a selective dielectric etch within the patterned opening to form a plurality of source/drain (S/D) cavities; depositing a source/drain contact metal in the S/D cavities to form a plurality of contact strips; forming a second mask layer comprising a plurality of regions disposed over a portion of the capping layer and a portion of an adjacent contact strip of the plurality of contact strips; performing an etch of the adjacent contact strip to form a source/drain contact.