Illumination unit and device for lithographic exposure
An illumination unit for lithographic exposure and a device for lithographic exposure are disclosed. In an embodiment the illumination unit includes a beam source, an electronically drivable beam deflection element for generating a temporally varying two-dimensional beam deflection, a collimation lens, a beam homogenizing element, a Fourier lens and a field lens.
1. An illumination unit for lithographic exposure comprising:
a beam source;
an electronically drivable beam deflection element for generating a temporally varying two-dimensional beam deflection;
a collimation lens;
a beam homogenizing element comprising:
an electronic driving assembly designed to move the beam homogenizing element during operation of the illumination unit; and
a plurality of diffractive optical elements which are arranged alongside one another in a 2-dimensional arrangement;
a Fourier lens; and
a field lens,
wherein light collimated by the collimation lens impinges perpendicularly on the beam homogenizing element, and
wherein the field lens is designed for a telecentric illumination of a photomask.
2. The illumination unit according to claim 1 , wherein the beam deflection element is a 2D mirror scanner.
3. The illumination unit according to claim 2 , wherein the 2D mirror scanner is a galvano scanner or a MEMS scanner.
4. The illumination unit according to claim 1 , wherein the beam deflection element has an electronic control unit by which an angle distribution of a beam deflection is settable.
5. The illumination unit according to claim 1 , wherein the beam homogenizing element is designed to perform a rotational movement about at least one axis and/or a translational movement in at least one direction during operation of the illumination unit.
6. The illumination unit according to claim 1 , wherein the beam source is a laser light source.
7. The illumination unit according to claim 1 , further comprising a polarizing optical element arranged between the beam source and the beam deflection element.
8. A device for lithographic exposure comprising:
an illumination unit according to claim 1 ; and
a photomask.
9. The device for lithographic exposure according to claim 8 , wherein the beam homogenizing element for generating a homogenous angle distribution of an illumination light impinging on the photomask is arranged in a Fourier plane of the photomask.