METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for manufacturing a semiconductor device is provided to decrease stress between a nitride layer on an isolation layer and an active region by forming a vacuum region between the active region and the isolation layer in forming a borderless contact, and to improve a junction leakage current characteristic by preventing a loss of the isolation layer. CONSTITUTION: A trench-type isolation layer(19b) is formed on a semiconductor substrate(11). A predetermined thickness of the isolation layer is removed to form a groove. A buffer high temperature low deposition(HLD) layer(21b) and the nitride layer are sequentially formed. The nitride layer is planarized, and the groove is buried. The nitride layer and the buffer HLD layer on the active region of the substrate are eliminated. A transistor composed of a gate electrode(27) and a source/drain electrode is formed on the active region, and an interlayer dielectric(37) is formed. The interlayer dielectric is etched to form a contact hole exposing the source/drain electrode and the isolation layer by using a contact mask exposing a portion of the substrate for a bit line contact. The buffer HLD layer between the source/drain electrode in the lower portion of the contact hole and the nitride layer on the isolation layer is eliminated. The contact hole is filled with a contact plug(41), and the vacuum region(39) is formed in a portion where the buffer HLD layer between the source/drain electrode and the nitride layer on the isolation layer is eliminated.