Patent ID: 6219130
Filing Date: 2001-04-17
Classification: G03F

Abstract:
A photo-lithographic system comprising more than one exposure apparatus including first and second exposure apparatuses,wherein the first exposure apparatus transfers a first pattern onto a substrate which has a first mark formed thereon, said first mark being covered with a first film having a light transmittance feature for transmitting light of a first wavelength band, said first exposure apparatus having a first detection device which directs a first illumination beam having a wavelength within said first wavelength band onto said first mark to attain information of the position of said first mark, andthe second exposure apparatus transfers a second pattern onto said substrate which has a second mark formed thereon, said second mark being covered with a second film having a light transmittance feature for transmitting light of a second wavelength band which is different from said first wavelength band, said second exposure apparatus having a second detection device which directs a second illumination beam having a wavelength within said second wavelength band onto said second mark to attain information of the position of said second mark.