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

Claim 2:
3. A semiconductor structure, comprising:
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;
a first spacer located above a second portion of the channel layer extending outwards from the metal gate stack, the first spacer being disposed between a bottom portion of the metal gate stack and portions of the source/drain regions located above the substrate; and
a contact structure above the source/drain regions, the contact structure being in contact with a second spacer disposed 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.