Abstract: The invention relates to a method for determining a critical dimension variation of a photolithographic mask which comprises (a) using layout data of the photolithographic mask to determine at least two sub-areas of the photolithographic mask, each sub-area comprising a group of features, (b) measuring a distribution of a transmission of each sub-area, (c) determining a deviation of the transmission from a mean transmission value for each sub-area, (d) determining a constant specific for each sub-area, and (e) determining the critical dimension variation of the photolithographic mask by combining for each sub-area the deviation of the transmission and the sub-area specific constant.

Abstract: A photo mask having a first set of patterns and a second set of patterns is provided in which the first set of patterns correspond to a circuit pattern to be fabricated on a wafer, and the second set of patterns have dimensions such that the second set of patterns do not contribute to the circuit pattern that is produced using a lithography process based on the first set of patterns under a first exposure condition. The critical dimension distribution of the photo mask is determined based on the second set of patterns that do not contribute to the circuit pattern produced using the lithography process based on the first set of patterns under the first exposure condition.

Abstract: The invention relates to a method for determining a critical dimension variation of a photolithographic mask which comprises (a) using layout data of the photolithographic mask to determine at least two sub-areas of the photolithographic mask, each sub-area comprising a group of features, (b) measuring a distribution of a transmission of each sub-area, (c) determining a deviation of the transmission from a mean transmission value for each sub-area, (d) determining a constant specific for each sub-area, and (e) determining the critical dimension variation of the photolithographic mask by combining for each sub-area the deviation of the transmission and the sub-area specific constant.

Abstract: A photo mask having a first set of patterns and a second set of patterns is provided in which the first set of patterns correspond to a circuit pattern to be fabricated on a wafer, and the second set of patterns have dimensions such that the second set of patterns do not contribute to the circuit pattern that is produced using a lithography process based on the first set of patterns under a first exposure condition. The critical dimension distribution of the photo mask is determined based on the second set of patterns that do not contribute to the circuit pattern produced using the lithography process based on the first set of patterns under the first exposure condition.

Abstract: A method for minimizing errors of a plurality of photolithographic masks that serve for successively processing a substrate is provided. The method includes determining a reference displacement vector field, in which the reference displacement vector field correlates displacement vectors of the errors of the plurality of photolithographic masks. The method includes determining for each of the photolithographic mask a difference displacement vector field as a difference between the reference displacement vector field and the displacement vectors of the errors of the respective photolithographic mask, and correcting the errors for each of the photolithographic masks using the respective difference displacement vector field.

Abstract: A lithographic mask comprises a first layer including grooves, a second layer including regions, sections and a groove-like structure that encloses the sections. The first and second layers are formed so as to reduce electrical potential differences within the second layer. A method of forming a lithographic mask includes forming first and second layers to dispose the second layer over the first layer, patterning the second layer to comprise sections, a region, and a groove-like structure enclosing the sections, and forming grooves in the first layer at portions not covered by the second layer. The first and second layers are formed to reduce potential differences within the second layers during the step of forming the grooves in the first layer.

Abstract: The invention relates to a method for minimizing errors of a plurality of photolithographic masks, the plurality of photolithographic masks serving for successively processing a substrate, the method comprises determining a reference displacement vector field, the reference displacement vector field correlates displacement vectors of the errors of the plurality of photolithographic masks, determining for each of the photolithographic mask a difference displacement vector field as a difference between the reference displacement vector field and the displacement vectors of the errors of the respective photolithographic mask, and correcting the errors for each of the photolithographic masks using the respective difference displacement vector field.

Abstract: 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.

Abstract: A lithographic mask comprises a first layer including grooves, a second layer including regions, sections and a groove-like structure that encloses the sections. The first and second layers are formed so as to reduce electrical potential differences within the second layer. A method of forming a lithographic mask includes forming first and second layers to dispose the second layer over the first layer, patterning the second layer to comprise sections, a region, and a groove-like structure enclosing the sections, and forming grooves in the first layer at portions not covered by the second layer. The first and second layers are formed to reduce potential differences within the second layers during the step of forming the grooves in the first layer.

Abstract: A layout is decomposed into partial patterns. An intermediate mask is drawn for each of the partial patterns. The intermediate masks are used in a mask stepper or scanner progressively for projection again into a common pattern on a test mask. A line width distribution LB(x,y) is determined from the test mask or from a test wafer exposed using the mask, and is converted into a distribution of dose corrections. The transmission T(x,y) of the respective intermediate masks is adapted based upon the calculated dose correction. This can be achieved using additional optical elements which are assigned to the intermediate masks and have shading structure elements, or by laser-induced rear-side introduction of shading elements in the quartz substrate of the intermediate masks themselves.

Abstract: 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.

Abstract: A reflection mask that includes a structure (20) for lithographically transferring a layout onto a target substrate, in particular for use in EUV lithography, and a reflective multilayer structure (11). At least one flare reduction layer (13?, 17) is at least partly arranged on a bright field of the multilayer structure (11).

Abstract: A photosensitive layer stack, lithographic systems and methods of patterning a substrate are disclosed having a patterning layer and a photochromic layer with an absorption switching from transmissive to absorptive upon exposure.

Abstract: A system for projecting a pattern from a mask onto a substrate comprises a radiation source for emitting a light beam in the extreme ultraviolet wavelength range, a mask including absorbent and reflective structures forming the pattern, a collector mirror and an illumination optical system forming a first part of a beam path in order to direct the light beam onto the mask to produce a patterned light beam, a projection optical system including an arrangement of reflective mirrors forming a second part of the beam path in order to focus the reflected light beam from the mask onto the substrate, and an optical element arranged in the beam path and including at least two regions having different degrees of reflection or transmission. First and second of the regions are assigned to respective different first and second positions on the mask and/or collector mirror in accordance with the beam path.

Abstract: A photosensitive layer stack and methods for multiple exposure lithography are disclosed having a bleachable layer with a first absorption switching from absorptive to transmissive upon irradiation and a photochromic layer having a second absorption switching from transmissive to absorptive upon irradiation.

Abstract: In a method of adjusting an optical parameter of an exposure apparatus, a photolithographic projection is performed using an exposure apparatus and using a layout pattern so as to provide measured layout data with different focus settings of the exposure apparatus. An optical model is provided including at least one optical parameter and a simulated image is created by using the optical model and the layout pattern. The optical model is optimized by modifying the optical parameter.

Abstract: A method for reducing an overlay error of structures of a layer to be patterned relative to those of a reference layer includes formation of standard measurement marks assigned to one another in the two layers for determining an overlay error and for setting up further measurement marks for determining an additional optical imaging error of the projection system at least in the current layer. The further measurement marks have a geometry adapted to the geometry of selected structures of the circuit patterns to be transferred by projection from masks onto semiconductor substrates. An imaging error affects circuit structures and further measurement marks in the same way. An alignment correction for a subsequent exposure can be calculated from the measured positional deviations between the two standard measurement marks and between the standard measurement mark and the further measurement mark of the layer currently to be patterned.

Abstract: Photolithography using polarized light is disclosed. For example, a method includes transmitting the light through a mask having a first area with a first class of patterns and a second area with a second class of patterns thereby generating a virtual image. The virtual image is exposed into a resist layer. The polarization of the light passing the first area is modified while the light passing the mask.

Abstract: A set of at least two masks for the projection of structure patterns coordinated with one another by a projection system into the same photosensitive layer of a semiconductor wafer, in which the set of at least two masks includes a primary mask having an opaque structure element, which is formed at a first position on the first mask. A second mask of the set, for example a trimming mask, which is assigned to the first mask, can have a semitransparent region assigned to the structure element of the first mask. The semitransparent region can be formed at the same position on the second mask as the opaque structure element on the first mask. With the aid of the suitable choice of the transparency of the semitransparent region, it is possible to enable an undesirable resist region to be trimmed away for enlargement of a process window during exposure of the photosensitive layer on the semiconductor wafer.

Abstract: A set of at least two masks, coordinated with one another, for the projection of structure patterns, into the same photosensitive layer arranged on a semiconductor wafer. The first mask includes a semitransparent or nontransparent first layer, which is arranged on a first substrate and in which at least one first opening is formed at a first position, the first opening having a first lateral dimension, which is greater than the resolution limit of a projection system for the projection of the structure patterns. The second mask includes a semitransparent or nontransparent second layer, which is arranged on a second substrate and in which at least one dummy structure assigned to the first opening is formed at a second position, the dummy structure having a second lateral dimension, which is smaller than the resolution limit of the projection system wherein the first position on the first mask corresponds to the second position on the second mask.