Semiconductor device inspection apparatus using a plurality of reflective elements

摘要

An improved optical inspection apparatus, especially suited for inspecting semiconductor devices using a single camera. A highly polished mirrored stage is provided with a light source extending upwardly therethrough and providing a pedestal upon which the object to be inspected is centered. A plurality of stationary reflectors are disposed around the stage and function in concert with two separate movable reflectors to provide optical scanning over the appropriate surface portions of the device. A separate movable reflector system is used to maintain a constant focal path length between the device and the camera as the other movable reflectors scan the device, thus ensuring proper focus and measurement accuracy.