Maintaining integrity of a high-K gate stack by an offset spacer used to determine an offset of a strain-inducing semiconductor alloy

摘要

In sophisticated transistor elements including a high-k gate metal stack, the integrity of the sensitive gate materials may be ensured by a spacer element that may be concurrently used as an offset spacer for defining a lateral offset of a strain-inducing semiconductor alloy. The cap material of the sophisticated gate stack may be removed without compromising integrity of the offset spacer by providing a sacrificial spacer element. Consequently, an efficient strain-inducing mechanism may be obtained in combination with the provision of a sophisticated gate stack with the required material integrity, while reducing overall process complexity compared to conventional strategies.