Abstract: The present invention is intended to highly fast, stably acquire highly accurate images from irradiated positions with an electron beam on a circuit pattern in the step of fabricating a semiconductor device including an insulating material or a mixture of an insulating material and a conductive material, without occurrence of any deviation in the irradiated position in the images to be comparatively inspected, automatically comparing the images with each other thereby inspecting defects of the circuit pattern without occurrence of errors, and feeding back the result to the conditions of fabricating the semiconductor device thereby increasing the reliability of the semiconductor device and reducing the defective percentage thereof.