Abstract:
A method of aligning an object may include obtaining a first actual image of a first pattern on the object, setting the first actual image as a first reference image, obtaining a second actual image of a second pattern on the object, comparing the second actual image with the first reference image to obtain first relative position difference values of the second actual image with respect to the first reference image, and converting the first relative position difference values into first absolute position difference values with respect to a reference point on the object.
Abstract:
An apparatus for measuring a mask error and a method for measuring a mask error are provided. The apparatus for measuring a mask error includes a stage configured to accommodate a reference mask having a reference pattern, and a target mask adjacent to the reference mask such that a mask pattern of the target mask faces the reference pattern, a light source configured to irradiate the first beam onto the reference mask and the target mask, a light receiving unit including an image sensor, and the image sensor configured to receive a composite image including a first image generated from the reference pattern and a second image generated from the mask pattern, and generate a third image from the first image and the second image, and a measuring unit configured to measure an error of the mask pattern from the third image.