Optical component for use in e.g. illumination device for micro-lithographic extreme UV-projection exposure system, has mirror unit immersed in medium and supported in floating manner under operational conditions

摘要

The component (32) has a mirror unit (34) comprising a mirror surface (36), and a bearing unit (52) provided in vacuum liquid medium (48) e.g. liquid metal such as mercury, liquid metal alloy, or galinstan(RTM: eutectic alloy). The mirror unit is partially immersed in the liquid medium and supported in a floating manner under operational conditions. An actuator (42) comprises a chamber (50) that is filled with the liquid medium and limited by a chamber housing (54). A sealing unit (60) seals the chamber in a liquid and gas tight manner, and a projection lens comprises housing.