Patent ID: 6187630
Filing Date: 2001-02-13
Classification: H01L

Abstract:
A method for forming hemispherical silicon grains on a silicon layer, comprising the steps of:providing a substrate, which has a dielectric layer on top, and has an opening in the dielectric layer to expose the substrate beneath the dielectric layer;forming a doped polysilicon layer over the substrate, wherein the doped polysilicon layer also fills the opening;patterning the doped polysilicon layer to remove an undesired portion;forming amorphous silicon spacers on sidewalls of the doped polysilicon layer;transforming an upper portion of the doped polysilicon layer into an amorphous silicon layer, wherein the amorphous silicon layer and the amorphous silicon spacer together cover the doped polysilicon layer; andforming hemispherical silicon grains on an exposed surface of the amorphous silicon spacers and an upper surface of the amorphous silicon layer lying above the doped polysilicon layer.