METHOD FOR MEASURING OVERLAY OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for measuring the overlay of a semiconductor device is provided to improve overlay accuracy by reducing the generation of noise by using a light source which is polarized in the overlay reading. CONSTITUTION: An overlay vernier(100) comprises a plurality of first vernier patterns(100a) and a plurality of second vernier patterns(100b). The first vernier pattern and the second vernier pattern are formed into a bar shape. The plurality of first vernier patterns is extended to a y-shaft direction and is arranged according to an x-shaft direction. The plurality of second vernier patterns is extended to the x-shaft direction and is arranged according to the y-shaft direction. A polarized light source(110) is irradiated on the overlay vernier. An image signal of the overlay vernier is read. An overlay value is measured through the image signal.