STRUCTURE AND METHOD TO FORM A THERMALLY STALE SILICIDE IN NARROW DIMENSION GATE STACKS

摘要

An integrated circuit is provided including a narrow gate stack having a width less than or equal to 65 nm, including a suicide region comprising Pt segregated in a region of the suicide away from the top surface of the suicide and towards an lower portion defined by a pulldown height of spacers on the sidewalls of the gate conductor. In a preferred embodiment, the spacers are pulled down prior to formation of the suicide. The suicide is first formed by a formation anneal, at a temperature in the range 250°C to 450°C. Subsequently, a segregation anneal at a temperature in the range 450°C to 550°C. The distribution of the Pt along the vertical length of the suicide layer has a peak Pt concentration within the segregated region, and the segregated Pt region has a width at half the peak Pt concentration that is less than 50% of the distance between the top surface of the suicide layer and the pulldown spacer height.