VARIABLE LENGTH MULTI-CHANNEL REPLACEMENT METAL GATE INCLUDING SILICON HARD MASK

摘要

A method of forming a semiconductor device includes forming first and second semiconductor structures on a semiconductor substrate. The first semiconductor structure includes a first gate channel region having a first gate length, and the second semiconductor structure including a second gate channel region having a second gate length that is greater than the first gate length. The method further includes depositing a work function metal layer in each of a first gate void formed at the first gate channel region and a second gate void formed at the second gate channel region. The method further includes depositing a semiconductor masking layer on the work function metal layer, and simultaneously etching the silicon masking layer located at the first and second gate channel regions to re-expose the first and second gate voids. A low-resistive metal is deposited in the first and second gate voids to form low-resistive metal gate stacks.

主权项

1. A multigate semiconductor device, comprising:
first and second semiconductor structures formed on a semiconductor substrate, the first semiconductor structure including a first gate channel region having a first gate length and the second semiconductor structure including a second gate channel region having a second gate length that is greater than the first gate length; a first work function metal layer formed in the first gate channel region and a second work function metal layer formed in the second gate channel region; the second work function metal layer including sidewall portions separated from one another by a base portion; and a first metal gate stack formed on the work function metal layer located at the first gate channel region and a second metal gate stack formed on the work function metal layer located at the second gate channel region, the second metal gate stack formed on upper portions of the sidewall portions.