)levelling method of wafer of reflection projection exposure device
Abstract
Abstract PURPOSE:To align the surface of a wafer without breaking a photosensitizer coating formed to the surface of the wafer by measuring a level of the surface of the wafer in a noncontact manner while measuring a reference surface through the measuring means for the level, comparing these measuring values, and vertically driving the wafer in the direction that the difference decreases when the surface of the wafer is aligned to the reference surface. CONSTITUTION:A travelling table 6 is fixed onto a surface plate 5, stages 3, 4 are placed on the table 6, and the wafer 1 is disposed onto the stage 3 and a mask 2 onto the stage 4 while a reference surface block 32 is positioned between the stages 3, 4. A projection optical system 7 and an alignment optical system 8 are installed onto these wafer, mask and block, and a level of the wafer 1 is detected by an objective 11 and a half mirror 12. The table 6 is moved to position the wafer 1 at the lower section of a surface positioning section 39 with a noncontact displacement meter, and the stage 3 is moved vertically through a means not shown while using a space between the positioning section and the block 32 as a reference.
Inventors
- 👤 Hidezo Sano
- 👤 秀造 佐野
- 👤 Minoru Ikeda
- 👤 稔 池田
Bibliographic Details
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