Patent ID: 9147572
Filing Date: 2015-09-29
Classification: H01L

Abstract:
1. A method comprising: removing a dummy gate from above a substrate forming a cavity, wherein side surfaces of the cavity are lined with an oxidized spacer layer and a bottom surface of the cavity is lined with a gate oxide layer; conformally forming a sacrificial oxide layer over the substrate and the cavity; removing the sacrificial oxide layer from the bottom surface of the cavity and the substrate via a reactive-ion etching for 8 to 20 seconds leaving sacrificial oxide spacers lining the side surfaces of the cavity; removing the gate oxide layer at the bottom of the cavity, exposing the substrate, and forming a high-k metal gate within the cavity; after removal of the gate oxide layer, performing an in-situ dry chemical cleaning of the cavity and the substrate, wherein the in-situ dry chemical cleaning increases a gate length of the cavity less than 3 nm.