PURPOSE: To observe the deepest part of a semiconductor readily without destruction, by forming the rear of a semiconductor substrate as a mirror surface, inputting light, which can be transmitted through the semiconductor substrate, and observing the reflected light from the inside.
CONSTITUTION: On the surface of a semiconductor substrate 10, e.g., a silicon oxide film 11 and an aluminum thin film 12 are formed by a semiconductor process. When the rear of the substrate 10 is rough, the fine state of the inside cannot be well observed. Therefore, the rear of the substrate 10 is made to be a mirror surface state. The inside of the substrate 10 is lighted by using a light source 30, a lens 20, a half mirror 22 and a lens 21. The state of the inside is observed by forming the image of the reflected light on an image sensing surface of a TV camera 20 through the lens 21. Thus the deepest part of the semiconductor can be readily observed without destruction.
MUNAKATA TADASUKE
HASE SHINOBU
