METHOD FOR FABRICATING CONDUCTIVE INTERCONNECTION OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for fabricating a conductive interconnection of a semiconductor device is provided to prevent misalignment and improve an electrical characteristic by etching a polycrystalline silicon layer while using an etch selectivity difference between the polycrystalline silicon layer and an underlying layer. CONSTITUTION: The first interlayer dielectric(33) having a lower metal interconnection(35) is formed on a semiconductor substrate(31). A diffusion barrier layer(37) is formed on the resultant structure. A sacrificial conductive layer is formed on the diffusion barrier layer. A sacrificial conductive layer pattern(40) is formed through a photolithography process using the sacrificial conductive layer as an upper metal interconnection mask wherein the lower sidewall of the sacrificial conductive layer pattern is etched to form a T-typed sacrificial conductive layer pattern in which a notching phenomenon occurs. The second interlayer dielectric exposing the sacrificial conductive layer patterns is formed on the resultant structure. The sacrificial conductive layer pattern is removed and the exposed diffusion barrier layer is etched to expose the lower metal interconnection so that a via contact hole and a trench are simultaneously formed. The via contact hole and the trench are filled to form an upper metal interconnection connected to the lower metal interconnection.