DIFFRACTION-OPTICAL COMPONENT, ILLUMINATION SYSTEM AND EXPOSURE SYSTEM COMPRISING THE SAME, AND METHOD FOR EXPOSURE EMPLOYING SUCH EXPOSURE

摘要

PURPOSE: Diffraction-optical component, illumination system and exposure system comprising the same, and method for exposure employing such exposur are provided to realize a diffraction-optical component for providing a radiation-diffracting grating structure with a high diffraction efficiency for short optical wavelengths. CONSTITUTION: Diffraction-optical component for providing a radiation-diffracting grating structure, comprising: a surface wave device including a substrate(43), a surface wave source(47) excitable with an adjustable frequency for producing surface waves on a surface(45) of the substrate(43) and an interaction region(17) of the substrate surface(45) which is provided for the radiation to interact with a grating structure provided by the surface waves produced, characterized in that the surface wave source(47) has a directional characteristic and emits surface waves stronger in a preferred direction(53) than in a direction opposite thereto, the surface waves emitted in the preferred direction(53) providing the grating structure.