| 摘要 |
PURPOSE:To enhance wafer mark image-formation contrast by placing a window mark near the X-ray mask mark. CONSTITUTION:A window mark U is overlaid near an X-ray mask mark and observed. The window mark U is formed so that the rectangular area in respects to the central mask Ma is made of transparent material and is shaped around the mask Ma and the section on this periphery is made of the same non-transparent material (TA or Au) as used for the mask mark Ma. The size of the window mark U is set to be nearly equal to the lumination region Q. The multiple, reflection light between the X-ray mask M and the wafer W is significantly reduced. As a result, the contrast and resolution of the wafer mark, which until now has been greatly diminished by this type of multiple, reflection light, is detected with almost no loss. |
