| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve the accuracy of a projection aligner by making the aligner easily adaptable to increased sizes of wafers and reducing the load deformation with a stage movement by using a ceramic material which has a light weight, high rigidity, and excellent shape stability for forming a supporting structure. SOLUTION: In this embodiment, the hatched support is constituted of a ceramic material, but a base 1a, a reticle support 4, and a light-source optical system 6a can also be constituted of the ceramic material in addition to a supporting frame 5. Practically, steel bars 9 are arranged longitudinally and latitudinally on the lower surface side in the top section 5a of the frame 5 which especially requires a breakdown strength to resist impact loads from the top side. The steel bars 9 can be arranged integrally with the top section 5a in sintering the ceramic material or can be inserted into preopened holes and coupled with each other after sintering the ceramic material. When the steel bars, etc., having a larger coefficient of thermal expansion than the ceramic material has are joined with the ceramic material in a hot state, the tensile stress of the support can be relieved.</p> |
