Texas Instruments Corporation

Chet Vernon Lenox

Brian Keith Kirkpatrick

Seung-Chul Song

James Walter Blatchford

An integrated circuit is formed by removing a sacrificial gate dielectric layer and a sacrificial gate to form a gate cavity. A conformal dielectric first liner is formed in the gate cavity and a conformal second liner is formed on the first liner. A first etch removes the second liner from the bottom of the gate cavity, leaving material of the second liner on sidewalls of the gate cavity. A second etch removes the first liner from the bottom of the gate cavity exposed by the second liner, leaving material of the first liner on the bottom of the gate cavity under the second liner on the sidewalls of the gate cavity. A third etch removes the second liner from the gate cavity, leaving an L-shaped spacers of the first liner in the gate cavity. A permanent gate dielectric layer and replacement gate are formed in the gate cavity.

Inner L-spacer for replacement gate flow

A method of forming PMOS transistors. A SiGe cavity formation process includes cavity etching a structure including a gate stack having a gate electrode on a gate dielectric on a substrate, a sidewall spacer, and a hardmask layer on the gate electrode. The cavity etching includes (i) a first anisotropic dry etch for etching through the hardmask layer lateral to the gate stack and beginning a recessed cavity in the substrate, (ii) a dry lateral etch, and (iii) a second anisotropic dry etch. A wet crystallographic etch completes formation of the recessed cavity. A customized time is calculated for a selected dry etch step from the plurality of dry etch steps based on in-process SiGe cavity data for a measured cavity parameter for a SiGe cavity formation process. The customized time for the selected dry etch is used to cavity etch at least one substrate in a lot or run.

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Venus, TX, United States of America

Chet Vernon Lenox