Method of forming contact plugs for eliminating tungsten seam issue

摘要

A method of forming a contact plug of an eDRAM device includes the following steps: forming a tungsten layer with tungsten seam on a dielectric layer to fill a contact hole; removing the tungsten layer from the top surface of the dielectric layer, recessing the tungsten layer in the contact hole to form a recess of about 600˜900 Angstroms in depth below the top surface of the dielectric layer, depositing a conductive layer on the dielectric layer and the recessed tungsten plug to fill the recess; and removing the conductive layer from the top surface of the dielectric layer to form a conductive plug on the recessed tungsten plug in the contact hole.