Infineon Technologies Ag

Qimonda Ag

Carl-zeiss-smt Ag

Thomas Muelders

Rainer Pforr

Toralf Gruner

Ulrich Wegmann

Vladimir Kamenov

Markus Mengel

Molela Moukara

Mario Hennig

Karsten Zeiler

Bernd Kuechler

Embodiments relate to compensating for lens heating, lithographic projection system and photo mask. Accordingly, lens heating is compensated by providing a layout pattern including a regular pattern being arranged substantially symmetrical in a first region and a sub-resolution pattern including a plurality of sub-resolution structural elements, wherein the sub-resolution pattern in a second region, so as to minimize non-homogenous lens heating of a projection apparatus in case of a lithographic projection.

Methods of compensating lens heating, lithographic projection system and photo mask

In a method for improving the imaging properties of a projection objective of a microlithographic projection exposure apparatus, an appropriate illumination angle distribution adapted to a mask () to be projected is selected. Then locations () in an exit pupil of the projection objective (), which are illuminated under these conditions by projection light during a projection of the mask, are determined. For at least one image point, an actual value of an imaging quantity, e.g. a wavefront profile or a polarization state, is determined that influences the imaging properties of the projection objective. Finally, corrective measures are calculated such that the actual value of the imaging quantity approximates a desired value at these locations. In this last step, however, deviations of the actual value from the desired value are taken into account exclusively at said locations illuminated in the exit pupil.

Method for improving the imaging properties of a projection objective for a microlithographic projection exposure apparatus

An improvement of the imaging quality with simultaneous transfer of line-space gratings and peripheral structures including a MUX space is achieved using a quadrupole illumination whose poles are formed in elongate fashion and whose longitudinal axes are arranged perpendicular to the orientation of the lines of the line-space grating arranged on a mask. The structure imaging of the line-space grating is improved with regard to contrast, MEEF, and process window, while the geometrical fidelity of the peripheral structure, in particular of the MUX space, is stabilized over a wide depth of field range.

Apparatus for projecting a pattern into an image plane

Growing community of inventors

Erding, Germany

Thomas Muelders