GCIB etching method for adjusting fin height of finFET devices

摘要

A gas cluster ion beam (GCIB) etching method for adjusting a fin height in finFET devices is described. The method includes providing a substrate having a fin structure and a gap-fill material layer completely overlying the fin structure and filling the regions between each fin of the fin structure, wherein each fin includes a cap layer formed on a top surface thereof, and planarizing the gap-fill material layer until the cap layer is exposed on at least one fin of the fin structure. Additionally, the method includes setting a target fin height for the fin structure, wherein the fin height measured from an interface between the cap layer and the fin structure, and exposing the substrate to a GCIB and recessing the gap-fill material layer relative to the cap layer until the target fin height is substantially achieved.

主权项

1. A gas cluster ion beam (GCIB) etching method for adjusting fin height in finFET devices, comprising:
providing a substrate having a fin structure and a gap-fill material layer completely overlying said fin structure and filling the regions between each fin of said fin structure, wherein each fin includes a cap layer formed on a top surface thereof; planarizing said gap-fill material layer until said cap layer is exposed on at least one fin of said fin structure; setting a target fin height for said fin structure, said fin height measured from an interface between said cap layer and said fin structure; establishing a GCIB from an etching process composition according to a process condition that achieves an etch selectivity in excess of 1.5, said etch selectivity being defined as a ratio between an etch rate of said gap-fill material layer and an etch rate of said cap layer; and exposing said substrate to said GCIB and recessing said gap-fill material layer relative to said cap layer until said target fin height is substantially achieved.