METAL CONTACT STRUCTURE OF SEMICONDUCTOR DEVICE AND FABRICATING METHOD THEREOF

摘要

PURPOSE: A metal contact structure of a semiconductor device is provided to prevent a void or key hole by broadening the upper portion of a contact hole, and to eliminate a problem of an ununiform etch-back process by using a barrier metal layer as an etch stop layer when the metal deposited for filling the contact hole is etched back. CONSTITUTION: An interlayer dielectric(130) is formed on a substrate(110) where a lower conductive layer(120) is formed. The interlayer dielectric is etched to form the contact hole exposing the lower conductive layer, wherein the diameter of the upper portion of the contact hole is broader than that of the lower portion of the contact hole. The barrier metal layer(150) is formed on the entire surface of the interlayer dielectric including the inside of the contact hole. The first metal is deposited on the barrier metal layer, but the inside of the contact is not completely filled with the first metal. The first metal is etched back while the barrier metal layer is used as an etch stop layer, so that a part of the first metal is left inside the contact hole and all of the first metal outside the contact hole is completely removed. The second metal is deposited on the resultant structure.