METHOD FOR RELIEVING STRESS OF INTERLAYER DIELECTRIC

摘要

PURPOSE: A method for relieving a stress of an interlayer dielectric is provided to reduce a stress of an HTUSG(High Temperature Undoped Silicate Glass) layer as an interlayer dielectric by performing a thermal process. CONSTITUTION: A buffer oxide layer(110) is deposited on a wafer(100). A silicon nitride layer(120) is deposited on the buffer oxide layer(110) by using a CMP(Chemical Mechanical Deposition) method. A silicon nitride layer is deposited on a back side of the wafer(100). A photo-resist pattern is formed on a predetermined portion of the silicon nitride layer(120). A silicon nitride layer pattern is formed by etching the silicon nitride layer(120). A trench is formed by etching the wafer(100). An oxide layer(140) is formed on a bottom and a side of the trench. An HTUSG layer as an interlayer dielectric is deposited thereon. The silicon nitride layer is removed by performing a back strip process. A thermal process for the interlayer dielectric(150) is performed.