Patent ID: 11876117
Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 9:
10. A method of forming a semiconductor structure, comprising:
forming a metal gate stack in contact with a first portion of a channel layer on a substrate, the first portion of the channel layer being located between source/drain regions;
forming a first spacer above a second portion of the channel layer extending outwards from the metal gate stack, the first spacer being formed between a bottom portion of the metal gate stack and portions of the source/drain regions located above the substrate;
forming a contact structure above the source/drain regions; and
forming a second spacer above the first spacer and between the contact structure and the metal gate stack, the second spacer including an airgap having a bottom portion that is wider than a top portion, wherein the wider bottom portion of the airgap is located between the metal gate stack and each of the source/drain regions, wherein the second spacer comprises a non-conformal dielectric material for pinching-off a space located above the first spacer and between the contact structure and the metal gate stack for forming the airgap.