Method of patterning a metal gate of semiconductor device

摘要

Provided are methods of patterning metal gate structures including a high-k gate dielectric. In an embodiment, a soluble hard mask layer may be used to provide a masking element to pattern a metal gate. The soluble hard mask layer may be removed from the substrate by water or a photoresist developer. In an embodiment, a hard mask including a high-k dielectric is formed. In a further embodiment, a protection layer is formed underlying a photoresist pattern. The protection layer may protect one or more layers formed on the substrate from a photoresist stripping process.

主权项

1. A method of fabricating a gate structure, comprising:
forming a gate dielectric layer on a semiconductor substrate, wherein the gate dielectric includes a first high-k dielectric; forming a metal layer on the gate dielectric layer; forming a hard mask layer on the metal layer, wherein the hard mask layer includes a second high-k dielectric; patterning the hard mask layer and the metal layer, wherein the patterning defines a first portion and a second portion of the gate dielectric layer, wherein the first portion underlies the hard mask and the second portion is in an open area of the substrate; removing the hard mask layer and the second portion of the gate dielectric layer; and after removing the hard mask layer and the second portion of the gate dielectric layer, forming another metal layer directly on the patterned metal layer and the open area.