| abstract |
A method of aligning a substrate includes forming a first alignment hole in the substrate, preparing a mask with a second alignment hole narrower than the first alignment hole, modifying a surface reflectance around either the first alignment hole or the second alignment hole to form a treatment region, positioning the mask below the substrate, such that the first and second alignment holes overlap, and operating a sensor unit above the first alignment hole to examine alignment of the first and second alignment holes. |