An overlay measurement method using a reference image is an effective method for an overlay measurement in a product circuit. However, there is a problem that it is not possible to obtain an ideal reference image in a process of prototyping.
A measurement device described in a specific embodiment of the present invention includes an imaging unit that captures an image of a circuit pattern of a semiconductor wafer surface by an optical microscope or an electronic microscope, a pattern recognition unit that extracts a first pattern and a second pattern from the image captured by the imaging unit, a reference image generation unit that synthesizes a first reference image using the first pattern extracted from a plurality of the images and synthesizes a second reference image using the second pattern extracted from the plurality of images, a quantification unit that quantifies a first difference that is a difference between the first reference image and the first pattern and a second difference that is a difference between the second reference image and the second pattern, and a calculation unit that calculates an overlay amount included in the circuit pattern using the first difference and the second difference.