Nanosheet MOSFET with full-height air-gap spacer
AssigneeInternational Business Machines Corporation
InventorsKangguo Cheng, Bruce B. Doris, Michael A. Guillorn, Xin Miao
Life of this patent
Estimating the term…
Abstract
A semiconductor device includes a gate positioned on a substrate; a nanosheet that extends through the gate, protrudes from a sidewall of the gate, and forms a recess between the substrate and the nanosheet; a dielectric spacer disposed in the recess; a source/drain contact positioned on a source/drain disposed on the substrate adjacent to the gate; an air gap spacer positioned along the sidewall of the gate and in contact with a dielectric material disposed on the nanosheet, the air gap spacer being in contact with the source/drain contact; and an interlayer dielectric (ILD) disposed on the air gap spacer.
Claims18
A method of making features of a semiconductor device, the method comprising:
- forming a nanosheet stack comprising a first nanosheet in contact with a substrate and a second nanosheet disposed on the first nanosheet;
- depositing a dielectric layer on the nanosheet stack;
- forming a gate comprising a sacrificial gate material on the nanosheet stack and the dielectric layer, a gate spacer positioned along a sidewall of the gate;
- removing an end portion of the first nanosheet to form a lateral recess beneath the gate spacer;
- depositing a dielectric material in the lateral recess;
- forming a source/drain on the substrate adjacent to the gate;
- replacing the sacrificial gate material with a conductive gate stack;
- removing remaining portions of the first nanosheet;
- and
- removing the gate spacer to expose the dielectric layer on the nanosheet stack and form an air gap spacer.
A method of making a semiconductor device, the method comprising:
- forming a nanosheet stack comprising a first nanosheet in contact with a substrate and a second nanosheet disposed on the first nanosheet;
- depositing a dielectric layer on the nanosheet stack;
- forming a gate comprising a sacrificial gate material on the nanosheet stack and the dielectric layer, a gate spacer positioned along a sidewall of the gate;
- removing an end portion of the first nanosheet to form a lateral recess beneath the gate spacer;
- depositing a dielectric material in the lateral recess;
- forming a source/drain on the substrate adjacent to the gate;
- replacing the sacrificial gate material with a conductive gate stack;
- removing remaining portions of the first nanosheet;
- and
- forming a source/drain contact on the source/drain and adjacent to the gate spacer;
- and
- removing the gate spacer to expose the dielectric layer on the nanosheet stack and form an air gap spacer.
Dependencies are inferred from the claim text.