SEMICONDUCTOR MEMORY DEVICE HAVING TWO-LAYERED METAL CONTACT STRUCTURE AND FABRICATING METHOD THEREOF

摘要

PURPOSE: A method for fabricating a semiconductor memory device having a two-layered metal contact structure is provided to guarantee an alignment margin of a metal contact in a peripheral region, by forming a stud in a layer except a bit line so that a sufficient stud formation space is guaranteed. CONSTITUTION: A gate electrode is formed on a semiconductor substrate. The first insulation layer is evenly formed on the semiconductor substrate. The stud formation space and the first metal contact hole are formed in the first insulation layer by consecutively performing isotropical and anisotropical etch processes. A conductive material is filled in the stud formation space and the first metal contact hole to form a stud(26B) and the first metal contact(26A). The second insulation of which the surface is flat is formed on the semiconductor substrate. A bit line contact hole is formed on the first and second insulation layers. A bit line(16) is formed on the second insulation layer having the bit line contact hole. The third insulation layer is formed on the semiconductor substrate having the bit line. A capacitor is formed in a cell region on the semiconductor substrate having the third insulation layer. The fourth insulation layer is formed on the semiconductor substrate having the capacitor. The second metal contact hole is formed in the second, third and fourth insulation layers to expose the stud. Metal is deposited on the fourth insulation layer to form the second metal contact(26C) in the second metal contact hole.