OVERLAY MARK AND METHOD FOR TESTING OF MASK ALIGN USING THE SAME

摘要

An overlay mark and a method for measuring mask alignment using the same are provided to enhance accuracy of alignment by forming a plurality of overlay marks to measure a lower layer. A plurality of outer overlay marks(200) are formed on a lower layer. An inner overlay mark(100) is formed on an upper layer within the outer overlay marks. The inner overlay mark is an overlay mark of a metal contact pattern. The outer overlay mark comprises an active layer overlay mark(210) and a gate layer overlay mark(220).