A method for removing polysilicon from isolation regions on a substrate during semiconductor fabrication is disclosed. The method includes depositing a layer of polysilicon over the substrate, and depositing at least one dielectric layer over the polysilicon. The method further includes polishing the polysilicon from the isolation regions, wherein the dielectric layers act as a polishing stop, resulting in regions of polysilicon that are self-aligned to the trench isolation regions.
J. F. Thomas, Kim, U., and K. Achuthan, “Self-aligned polysilicon polish”. 2003.