METHOD FOR FABRICATING METAL INTERCONNECTION BY DUAL DAMASCENE PROCESS

摘要

PURPOSE: A method for fabricating a metal interconnection by a dual damascene process is provided to form the profile of a desired etch target by forming the first silylation layer on the first photoresist layer pattern and by forming the second silylation layer on the second photoresist layer pattern in the same method as the first silylation layer. CONSTITUTION: An interlayer dielectric(23) is formed on a semiconductor substrate(21) having an underlying layer. The first photoresist layer pattern(25) corresponding to a contact region is formed on the interlayer dielectric. The first silylation layer(27) is formed on the first photoresist layer pattern. The second photoresist layer pattern(29) corresponding to the metal interconnection is formed on the first silylation layer. The first silylation layer is formed on the second photoresist layer pattern. The second silylation layer(31) and the first silylation layer not covered with the second silylation layer are removed while the interlayer dielectric is etched to define a contact hole region. The photoresist layer pattern not covered with the first silylation layer is eliminated. The first silylation layer and the interlayer dielectric not covered with the first silylation layer are etched to form a trench for the metal interconnection and a contact hole exposing the substrate. The photoresist layer pattern is removed. A metal layer is deposited on the resultant structure to fill the contact hole and the trench. The metal layer is planarized to form the metal interconnection until the interlayer dielectric is exposed.