Patent ID: 8891732

Claim:
An apparatus for detecting a mark in a layer of a semiconductor device, the apparatus comprising: an X-ray emitter for emitting an X-ray; an X-ray detector; an optical element configured to at least partially reflect the X-ray emitted from said X-ray emitter towards said semiconductor device; and a supporting member configured to support said semiconductor device and comprising a first X-ray reflector, wherein said X-ray detector is configured to detect at least one of a position of said mark and a shape of said mark using a signal related to a transmitted portion of the X-ray that has been transmitted through the semiconductor device supported on said supporting member, wherein said first X-ray reflector is configured to at least partially reflect said transmitted portion of the X-ray to produce a reflected portion of the X-ray, and wherein said X-ray detector comprises a conversion device configured to convert, without using visible light, said portion of the X-ray to an electric signal.