OVERLAY MEASURING METHODS AND SYSTEM, AND METHOD OF MANUFACTURING A SEMICONDUCTOR DEVICE USING THE SAME

摘要

In an overlay measuring method, an electron beam is irradiated onto a sample of a multilayer structure formed on upper and lower patterns which are overlapped with each other. So, a real image of the upper and the lower patterns is obtained. A first image which represents the upper pattern, and a second image which represents the lower patter are obtained from the real image. A reference position of the upper and the lower patterns is set from a design image of the upper and the lower patterns. A position deviation of the upper pattern of the first image and a position deviation of the lower pattern of the second image with respect to the reference position are calculated. So, an overlay between the upper pattern and the lower pattern is determined.