METHOD FOR FORMING OVERLAY MARK OF SEMICONDUCTOR DEVICE BY SELF-ALIGNMENT METHOD WITHOUT ADDITIONAL ETCH PROCESS

摘要

PURPOSE: A method for forming an overlay mark of a semiconductor device is provided to facilitate a process for fabricating the semiconductor device by forming a larger trench in the position of a measurement mark region and by forming a measurement mark in the trench wherein the overlay mark with a step is formed by a self-alignment method without an additional etch process. CONSTITUTION: A trench is formed which includes an overlay mark region of a semiconductor substrate(41). A predetermined thickness of a lower insulation layer(45) is formed on the resultant structure and is patterned by using an exposure mask for an outer box. A predetermined thickness of a conductive layer(47) is formed on the resultant structure. A predetermined thickness of an interlayer dielectric(49) is formed on the resultant structure. An opaque layer(51) is formed on the interlayer dielectric. The outer box that is formed by transcribing a step formed in the lower part of the trench is fabricated by the lower insulation layer. An inner box(53) is formed in the center of the outer box.