METHOD FOR FORMING METAL INTERCONNECTION OF SEMICONDUCTOR DEVICE TO PREVENT BRIDGE PHENOMENON BETWEEN METAL INTERCONNECTIONS

摘要

PURPOSE: A method for forming a metal interconnection of a semiconductor device is provided to prevent a bridge phenomenon between metal interconnections by forming a TEOS(tetraethoxysilane) layer as a hard mask before a photoresist layer is formed and by performing a physical etch process for strongly acting upon etch byproducts of metal. CONSTITUTION: A semiconductor substrate(31) is prepared which includes an insulation layer with a conductive plug(35). A metal layer for forming a metal interconnection in which the first Ti/TiN layer(36), an aluminium layer(37) and the second Ti/TiN layer(38) are sequentially stacked is formed on the substrate. A hard mask layer is formed on the metal layer. A photoresist layer pattern(50) of a predetermined type is formed on the hard mask layer to cover a part of the hard mask layer corresponding to at least the conductive plug. The hard mask layer is firstly etched by using the photoresist layer pattern as a mask. The metal layer is secondly etched to form a metal interconnection by using the photoresist layer pattern and the remaining hard mask layer as a mask. The photoresist layer pattern is eliminated.