Ultra-scale gate cut pillar with overlay immunity and method for producing the same
AssigneeGlobalfoundries Inc.
InventorsHui Zang, Josef Watts, Ruilong Xie
Life of this patent
Estimating the term…
Abstract
Methods of forming a self-aligned CT pillar with the same CD width as the device fins to enable PC isolation and the resulting devices are provided. Embodiments include forming a plurality of fins over a substrate; forming an oxide layer over the substrate and between each fin; removing a portion of a central fin among the plurality, a trench formed in the oxide layer; forming a CT pillar in the trench; recessing the oxide layer below an upper surface of the plurality of fins; forming a gate over the plurality of fins and CT pillar; planarizing the gate down to the CT pillar; and forming a cap layer over the gate and CT pillar.
Claims20
A method comprising:
- forming a plurality of fins over a substrate;
- forming an oxide layer over the substrate and between each fin;
- removing a portion of a central fin among the plurality, a trench formed in the oxide layer;
- forming a gate cut (CT) pillar in the trench;
- recessing the oxide layer below an upper surface of the plurality of fins;
- forming a gate over the plurality of fins and CT pillar;
- planarizing the gate down to the CT pillar;
- and
- forming a cap layer over the gate and CT pillar.
A device comprising:
- a plurality of fins over a substrate;
- an oxide layer over the substrate and between a portion of each fin;
- a gate cut (CT) pillar over a central fin among the plurality, a lower surface of the CT pillar being below an upper surface of the oxide layer;
- a gate over the plurality of fins and CT pillar;
- and
- a cap layer over the gate and CT pillar.
A method comprising:
- forming a first oxide layer over a substrate;
- forming a first silicon nitride (SiN) layer over the oxide layer;
- forming a trench through the first SiN and oxide layers and a portion of the Si substrate;
- forming a second oxide layer in and along sidewalls of the trench;
- recessing the second oxide layer between an upper surface of the substrate and an upper surface of the first oxide layer;
- filling the trench with a second SiN layer;
- forming a plurality of first and second SiN layer mandrels laterally separated over the substrate;
- removing equal portions of the second SiN layer in the trench on opposite sides of a second SiN layer mandrel;
- forming a plurality of fins and a gate cut (CT) pillar laterally centered therebetween over the substrate;
- forming an third oxide layer over the substrate and between a portion of the plurality of fins and CT pillar;
- forming a gate over the plurality of fins and CT pillar;
- planarizing the gate down to the CT pillar;
- and
- forming a cap layer over the gate and CT pillar.
A device comprising:
- a plurality of fins over a substrate, the substrate having a laterally centered trench;
- a first oxide layer in and along sidewalls of the trench;
- a gate cut (CT) pillar laterally centered over the trench and having a base over and along sidewalls of the first oxide layer;
- a second oxide layer over the substrate and between the fins and CT pillar, an upper surface of the second oxide layer below an upper surface of the fins;
- a gate over the plurality of fins and CT pillar;
- and
- a cap layer over the gate and CT pillar.
Dependencies are inferred from the claim text.