Exposure method

Abstract

An exposure method for transferring a pattern on a mask onto a photosensitive substrate. The exposure method has steps of (1) preparing the mask with a first alignment mark and the substrate with a second alignment mark, a length of the first alignment mark in a scan direction being shorter than a length of the second alignment mark in the same direction; (2) scanning the first and second alignment marks; (3) detecting an intensity of the light which has been emitted from the light source optical system and irradiated the mask and the substrate; (4) calculating an amount of dislocation between the first and second alignment marks in the scan direction; (5) correcting the dislocation between the mask and the substrate; (6) effecting an exposure to transfer the pattern on the mask onto the substrate.

What is claimed is: 
     
       1. An exposure apparatus for transferring a pattern on a photosensitive substrate, comprising: a mask stage which holds a mask on which said pattern and a first alignment mark are formed, said first alignment mark being a light shielding type mark;   a substrate stage which holds said photosensitive substrate having a second alignment mark longer in a predetermined direction that said first alignment mark so that said second alignment mark is corresponding to said first alignment mark;   a scanning mechanism which scans a light beam along said predetermined direction so as to traverse at least said first alignment mark, said second alignment mark being illuminated with said light beam which passes near said first alignment mark in a scanning of said scanning mechanism;   a first detector which detects said light beam reflected on said second alignment mark; and   an operating unit which calculates an amount of dislocation between said make and said photosensitive substrate.   
     
     
       2. An exposure apparatus according to claim 1, further comprising: a driving unit for driving at least one of said mask stage and said substrate stage on the basis of a calculated result of said operating unit to correct the relative positional relationship between said mask and said substrate. 
     
     
       3. An exposure apparatus according to claim 1, wherein a shape of said light beam is determined depending on that of said first alignment mark. 
     
     
       4. An exposure apparatus according to claim 3, wherein an illuminated size of said light beam is smaller than a size of said first alignment mark. 
     
     
       5. An exposure apparatus according to claim 1, wherein said first alignment mask blocks off said light beam when said light beam is on said first alignment mark and said first detector does not substantially detect said light beam from said second alignment mark. 
     
     
       6. An exposure apparatus according to claim 1, wherein a plurality of said second alignment marks are formed along a direction substantially perpendicular to said predetermined direction. 
     
     
       7. An exposure apparatus according to claim 1, wherein said scanning mechanism has an optical member and said scanning of said beam is performed by movement of said optical member. 
     
     
       8. An exposure apparatus according to claim 7, further comprising: a second detector which detects a position of said optical member. 
     
     
       9. An exposure apparatus according to claim 1, wherein scanning of said scanning mechanism is performed only one time for obtaining said amount of dislocation. 
     
     
       10. An alignment method comprising the steps of: arranging a mask on which a pattern and a first alignment mark of a light shielding type are formed;   arranging a photosensitive substrate having a second alignment with a length longer in a predetermined direction than that of said first alignment mark so that said second alignment mark is corresponding to said first alignment mark;   scanning light beam along said predetermined direction so as to traverse at least said first alignment mark, said second alignment mark being illuminated with said light beam which passes near said first alignment mark in a scanning of said scanning step;   detecting said light beam reflected on said second alignment mark;   obtaining an amount of dislocation between said mask and said photosensitive substrate on the basis of a detected result obtained in said detecting step; and   adjusting the relative position between said mask and said photosensitive substrate on the basis of said amount of dislocation.   
     
     
       11. An alignment method according to claim 10, wherein a shape of said light beam is determined depending on a shape of said first alignment mark. 
     
     
       12. An alignment method according to claim 11, wherein a size of said light beam is smaller than that of said first alignment mark. 
     
     
       13. An alignment method according to claim 10, wherein a plurality of said second alignment marks are formed along a direction substantially perpendicular to said predetermined direction. 
     
     
       14. An alignment method according to claim 10, wherein only one scanning is performed for obtaining the amount of dislocation.