METHOD FOR FORMING A CONTACT PLUG IN SEMICONDUCTOR DEVICE

摘要

A method for forming a contact plug of a semiconductor device is provided to improve contact failure between a lower conductive layer and an upper conductive layer by forming an etch stop layer on a dielectric exposed to both sides of the lower conductive layer. A semiconductor substrate on which a first dielectric(110) is formed is provided. A conductive layer(112) is formed in the first dielectric so that a part of the conductive layer is projected to an upper portion of the first dielectric. An etch stop layer(114) is deposited along a step of the upper portion of the first dielectric including the conductive layer. A second dielectric(115) is deposited on the etch stop layer. The second dielectric and the etch stop layer are etched to form a contact hole(118) exposing the part of the conductive layer. A contact plug is formed to gap-fill the contact hole.