Illumination system of a microlithographic projection exposure apparatus having a temperature control device

摘要

An illumination system of a microlithographic projection exposure apparatus includes a primary light source, a system pupil surface and a mirror array. The mirror array is arranged between the primary light source and the system pupil surface. The mirror array includes a plurality of adaptive mirror elements. Each mirror element includes a mirror support and a reflective coating. Each mirror element is configured to direct light produced by the primary light source towards the system pupil surface. The mirror elements can be tiltably mounted with respect to a support structure. The mirror elements include structures having a different coefficient of thermal expansion and being fixedly attached to one another. A temperature control device is configured to variably modify the temperature distribution within the structures to change the shape of the mirror elements.

主权项

1. An illumination system, comprising:
a mirror array comprising a plurality of mirror elements, each mirror element comprising:
a mirror support; anda reflective coating attached to the mirror support; and a temperature control device, wherein:
for each mirror element, the reflective coating has a coefficient of thermal expansion which is different from a coefficient of thermal expansion of the mirror support;for each mirror element, the temperature control device is configured so that, during use of the temperature control device, the temperature control device variably modifies a temperature distribution within the mirror support and the reflective coating to individually change a shape of the mirror element;for each mirror element, optical axes of the mirror element define an angle of more than 20° with an optical axis of a mirror which immediately precedes the mirror array in a propagation direction of light through the illumination system during use of the illumination system;the illumination system is configured to be used with light having a wavelength below 50 nm; andthe illumination system is a microlithographic illumination system.