ALIGNMENT MARK POSITION DETECTION

摘要

PURPOSE:To facilitate highly accurate detection of an alignment mark by a method wherein the alignment mark and a foundation are scanned by a focused ion beam and a radiation beam is created from the alignment mark or from the foundation or different radiation beams are created from both the alignment mark and the foundation. CONSTITUTION:An alignment mark 2 and a foundation 1 are scanned by a focused ion beam (FIB) 4 which is set to have a predetermined energy applied through resist 3. In the above description, a predetermined energy means the energy which is high enough to produce a radioactive substance at a collision point 7a and not high enough to produce a radioactive substance at a collision point 7b by utilizing the fact that the film thickness of the resist 3 on the alignment mark 2 is smaller than the film thickness of the resist 3 on the foundation 1 and the energy of the FIB 4 is reduced while it is passing through the resist 3. The radiation emitted from the produced radioactive substance is detected. The alignment mark and the foundation may be made of different materials. With this constitution, the alignment mark position can be detected with high accuracy by detecting the radiation with high sensitivity.