METHOD FOR FABRICATING SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for fabricating a semiconductor device is provided to prevent a characteristic of the semiconductor device from being deteriorated by a heat treatment process by forming a contact plug in a portion reserved for a bitline contact and a storage electrode contact in a cell region of a semiconductor substrate and by forming a source/drain region on a peripheral circuit region. CONSTITUTION: A gate electrode(17) is formed on the cell region and the peripheral circuit region of the semiconductor substrate(11). The first insulation layer is formed on the resultant structure by a predetermined thickness. A lightly-doped-drain(LDD) region(14) is formed on the resultant structure. The first interlayer dielectric(23) is formed on the resultant structure. The first interlayer dielectric and the first insulation layer are etched by using a contact mask as an etch mask such that the contact mask exposes bitline and storage electrode contact regions in the cell region. A conductive layer(27) is formed on the resultant structure. The first interlayer dielectric on the peripheral circuit region is removed. The second insulation layer is formed on the resultant structure. The second and first insulation layers are blanket-etched to form an insulation layer spacer. High density impurity ions are implanted into the substrate at both sides of the insulation layer spacer to form a source/drain region. The second interlayer dielectric is formed on the resultant structure. The second interlayer dielectric, the first interlayer dielectric and the conductive layer are planarization-etched to form a contact plug.