Mask structure and mask holding mechanism for exposure apparatus

摘要

A mask holding system includes a chucking mechanism for holding a mask structure including a frame and a mask substrate having a rectangular window with a mask pattern, and a load mechanism for applying, at a position along an extension of a diagonal of the rectangular window, a load to the frame in a direction along the plane of the mask, whereby the mask pattern can be distorted isotropically with the application of the load along the mask plane.