SELECTIVELY FORMING A PROTECTIVE CONDUCTIVE CAP ON A METAL GATE ELECTRODE

摘要

A replacement gate structure that includes a conductive metal gate electrode is formed in a gate cavity, wherein the gate cavity is formed in a dielectric material formed above an active region of a semiconductor device. An upper surface of the conductive metal gate electrode and an upper surface of the dielectric material are planarized during a common planarization process, and a protective conductive cap is selectively formed on and in direct physical contact with the planarized upper surface of the conductive metal gate electrode. A contact structure is formed in a dielectric insulating layer formed above the replacement gate structure, the contact structure directly contacting the protective conductive cap.

主权项

1. A method, comprising:
forming a replacement gate structure comprising an HK/MG material layer stack and a conductive metal gate electrode in a gate cavity, wherein said gate cavity is formed in a dielectric material formed above an active region of a semiconductor device, and wherein said HK/MG material layer stack is formed between said conductive metal gate electrode and sidewall and bottom surfaces of said gate cavity, said HK/MG material layer stack comprising a high-k dielectric material and a work function metal material formed above said high-k dielectric material; planarizing an upper surface of said conductive metal gate electrode, an upper surface of said HK/MG material layer stack, and an upper surface of said dielectric material during a common planarization process; selectively forming a protective conductive cap on and in direct physical contact with said planarized upper surface of said conductive metal gate electrode, wherein said protective conductive cap is substantially confined to said planarized upper surface of said conductive metal gate electrode and is not formed on and in direct physical contact with planarized upper surface portions of said high-k dielectric material or said work function metal material of said HK/MG material layer stack; and forming a contact structure in a dielectric insulating layer formed above said replacement gate structure, said contact structure directly contacting said protective conductive cap.