METHOD FOR MANUFACTURING A SEMICONDUCTOR MEMORY DEVICE

摘要

PURPOSE: A method for manufacturing a semiconductor memory device is provided to prevent an operation error, by preventing wafer contamination and pattern defects caused by pattern lifting. CONSTITUTION: An interlayer dielectric is formed on a semiconductor substrate(1) including a main cell region where a capacitor is to be formed and a key pattern formation region located in a predetermined portion on a scribe line. A conductive layer and an insulating layer are sequentially formed on the interlayer dielectric, and are patterned with a predetermined pattern to form a bit line(3) in the main cell region and a predetermined key pattern in the key pattern formation region. A buffering oxide layer(5) and a nitride layer(6) are sequentially formed on the entire surface including the bit line and key pattern. The nitride layer in the key pattern formation region is selectively etched to form a nitride layer spacer(6A) on a side wall of the key pattern. A sacrificial oxide layer(8) is formed on the entire surface. The sacrificial oxide layer and a part of the nitride layer in the main cell region are selectively etched to expose a predetermined portion of the substrate while a nitride layer spacer is formed on a side of the bit line located in a predetermined region of the main cell region. A polyslicon layer for a storage node is deposited, and is selectively etched to form a polysilicon pattern on the key pattern. A storage node is formed, and the sacrificial oxide layer is removed.