REDUCING GATE EXPANSION AFTER SOURCE AND DRAIN IMPLANT IN GATE LAST PROCESS

摘要

A semiconductor structure includes a semiconductor substrate, an active region and a dummy gate structure disposed over the active region. A sacrificial conformal layer, including a bottom oxide layer and a top nitride layer are provided over the dummy gate structure and active region to protect the dummy gate during source and drain implantation. The active region is implanted using dopants such as, a n-type dopant or a p-type dopant to create a source region and a drain region in the active region, after which the sacrificial conformal layer is removed.

主权项

1. A method, comprising:
providing a semiconductor structure, the structure comprising: a semiconductor substrate; an active region for a source region, a drain region and a channel region therebetween; and a dummy gate over the channel region, the dummy gate comprising at least one dummy gate material; creating a sacrificial conformal protective layer over the dummy gate, the source region and the drain region; implanting one or more impurities through the sacrificial conformal layer to create the source region and the drain region; and removing the sacrificial conformal layer after the implanting.