Abstract: The invention relates to a method for measuring structures on masks (1) for photolithography, wherein firstly the mask (1) is mounted on a spatially movable platform (2). The position of the platform (2) is controlled in this case. The structure on the mask (1) is illuminated with illumination light from an illumination light source which emits coherent light. The light coming from the mask (1) is imaged onto a detection device (6) by an imaging optical unit (4) and detected. The detected signals are evaluated in an evaluation device (7) and the positions and dimensions of the structures are determined. The invention also relates to an apparatus by which these method steps, in particular, can be carried out. In this case, the accuracy of the position and dimension determination is increased by the properties of the illumination light being coordinated with the structure to be measured.

Abstract: Disclosed is a method of modifying of a surface of a substrate of a photolithographic mask for extreme ultraviolet radiation comprising the step of focusing femtosecond light pulses of a laser system onto the substrate so that a plurality of color centers is generated inside the substrate, wherein the color centers are distributed to cause a modification of the substrate surface.

Abstract: A method for measuring the relative local position error of one of the sections of an object that is exposed section by section, in particular of a lithography mask or of a wafer, is provided, each exposed section having a plurality of measurement marks, wherein a) a region of the object which is larger than the one section is imaged in magnified fashion and is detected as an image, b) position errors of the measurement marks contained in the detected image are determined on the basis of the detected image, c) corrected position errors are derived by position error components which are caused by the magnified imaging and detection being extracted from the determined position errors of the measurement marks, d) the relative local position error of the one section is derived on the basis of the corrected position errors of the measurement marks.

Abstract: The invention relates to a method and an apparatus for measuring masks for photolithography. In this case, structures to be measured on the mask on a movable mask carrier are illuminated and imaged as an aerial image onto a detector, the illumination being set in a manner corresponding to the illumination in a photolithography scanner during a wafer exposure. A selection of positions at which the structures to be measured are situated on the mask is predetermined, and the positions on the mask in the selection are successively brought to the focus of an imaging optical system, where they are illuminated and in each case imaged as a magnified aerial image onto a detector, and the aerial images are subsequently stored. The structure properties of the structures are then analyzed by means of predetermined evaluation algorithms. The accuracy of the setting of the positions and of the determination of structure properties is increased in this case.

Abstract: A method is provided for determining the position of a structure within an image relative to a reference point, in which the structure has a center of symmetry, the method comprising: providing an image which comprises the structure and which has a reference point, carrying out at least one symmetry operation of the image with respect to the reference point, by means of which at least one mirror image is obtained which has a mirrored structure congruent relative to the structure, determining at least one displacement vector between a structure and a mirrored structure or two mirrored structures, and calculating the position of the structure as a position of the center of symmetry of the structure relative to the reference point from the at least one displacement vector. Furthermore, a position measuring device is provided for determining the position of a structure within an image relative to a reference point.

Abstract: The invention relates to a method for analyzing masks for photolithography. In this method, an aerial image of the mask for a first focus setting is generated and stored in an aerial image data record. The aerial image data record is transferred to an algorithm that simulates a photolithographic wafer exposure on the basis of this data record. In this case, the simulation is carried out for a plurality of mutually different energy doses. Then, at a predetermined height from the wafer surface, contours which separate regions with photoresist from those regions without photoresist are in each case determined. The result, that is to say the contours, are stored for each of the energy doses in each case in a contour data record with the energy dose as a parameter.

Abstract: The invention relates to a mask inspection method that can be used for the design and production of masks, in order to detect relevant weak points early on and to correct the same. According to said method for mask inspection, an aerial image simulation, preferably an all-over aerial image simulation, is carried out on the basis of the mask design converted into a mask layout, in order to determine a list of hot spots. The mask/test mask is analysed by means of an AIMS tool, whereby real aerial images are produced and compared with the simulated aerial images. The determined differences between the aerial images are used to improve the mask design. The inventive arrangement enables a method to be carried out for mask inspection for mask design and mask production. The use of the AIMS tool directly in the mask production process essentially accelerates the mask production, while reducing the error rate and cost.

Abstract: A method is provided for determining the position of a first structure (8a) relative to a second structure (8b) or a part thereof, said method having the steps of: a) providing a first picture (F1) having a multiplicity of pixels and which contains the first structure, b) providing a second picture (F2) having a multiplicity of pixels and which contains the second structure, c) forming an optimization function with the displacement of the two pictures relative to one another as parameter, the optimization function overlying the two pictures and masking the overlay such that in a determination of an extreme value of the optimization function a contribution is made only by the region of the overlay that corresponds to the second structure or the part thereof, d) ascertaining the extreme value of the optimization function and determining the optimal value of the displacement based on the extreme value of the optimization function, and e) determining the position of the first structure relative to the second stru

Abstract: A method and an apparatus for determining the position of a structure on a mask for microlithography, in which the position is determined by comparing an aerial image, measured by a recording device, of a portion of the mask with an aerial image determined by simulation. The position determination includes carrying out a plurality of such comparisons which differ from one another with regard to the input parameters of the simulation.

Abstract: The invention relates to a method for analyzing a defect of a photolithographic mask for an extreme ultraviolet (EUV) wavelength range (EUV mask) comprising the steps of: (a) generating at least one focus stack relating to the defect using an EUV mask inspection tool, (b) determining a surface configuration of the EUV mask at a position of the defect, (c) providing model structures having the determined surface configuration which have different phase errors and generating the respective focus stacks, and (d) determining a three dimensional error structure of the EUV mask defect by comparing the at least one generated focus stack of the defect and the generated focus stacks of the model structures.

Abstract: The invention relates to a method for correcting at least one error on wafers processed by at least one photolithographic mask, the method comprises: (a) measuring the at least one error on a wafer at a wafer processing site, and (b) modifying the at least one photolithographic mask by introducing at least one arrangement of local persistent modifications in the at least one photolithographic mask.

Abstract: The invention relates to a method for electron beam induced etching of a layer contaminated with gallium, with the method steps of providing at least one first halogenated compound as an etching gas at the position at which an electron beam impacts on the layer, and providing at least one second halogenated compound as a precursor gas for removing of the gallium from this position.

Abstract: The present method relates to processes for the removal of a material from a sample by a gas chemical reaction activated by a charged particle beam. The method is a multiple step process wherein in a first step a gas is supplied which, when a chemical reaction between the gas and the material is activated, forms a non-volatile material component such as a metal salt or a metaloxide. In a second consecutive step the reaction product of the first chemical reaction is removed from the sample.

Abstract: A method for calibrating an apparatus for the position measurement of measurement structures on a lithography mask comprises the following steps: qualifying a calibration mask comprising diffractive structures arranged thereon by determining positions of the diffractive structures with respect to one another by means of interferometric measurement, determining positions of measurement structures arranged on the calibration mask with respect to one another by means of the apparatus, and calibrating the apparatus by means of the positions determined for the measurement structures and also the positions determined for the diffractive structures.

Abstract: A method is provided for characterizing a mask having a structure, comprising the steps of: —illuminating said mask under at least one illumination angle with monochromatic illuminating radiation, so as to produce a diffraction pattern of said structure that includes at least two maxima of adjacent diffraction orders, —capturing said diffraction pattern, —determining the intensities of the maxima of the adjacent diffraction orders, —determining an intensity quotient of the intensities. A mask inspection microscope for characterizing a mask in conjunction with the performance of the inventive method is also provided.

Abstract: An irradiation module for a measuring apparatus is provided. The irradiation module is light-conductive, is configured as a cohesive body and comprises a beam-splitting surface arranged within the irradiation module for splitting an incoming measuring beam into two partial beams. Furthermore, the irradiation module comprises an optical diffraction grating for interaction with a first of the two partial beams and a reflection surface for reflecting the second partial beam.

Abstract: A method for verifying repairs on masks for photolithography is provided. A mask fabricated based on a mask layout is inspected for defects, and the positions at which defects are found on the mask are stored in a position file. In a repair step, the defects are repaired and, for each repaired position, in a verification step, an aerial image of the mask is taken at that position and the aerial image is analyzed to determine whether at that position the mask meets tolerance criteria established for one or more selected target parameters, and if the tolerance criteria have been met, the repair is verified. The verification can include a) based on the position file, a desired structure is defined in the mask layout at the repaired position, b) an aerial image is simulated for the desired structure, c) the captured aerial image is compared with the simulated one, and d) based on the comparison, a decision is made as to whether the repair at that position is verified.

Abstract: A method for calibrating a specimen stage of a metrology system is provided, in which a specimen that has multiple marks is positioned successively in different calibration positions, each mark is positioned in the photography range of an optical system by means of the specimen stage in each calibration position of the specimen, and the mark position is measured using the optical system. A model is set up that describes positioning errors of the specimen stage using a system of functions having calibration parameters to be determined. The model takes into consideration at least one systematic measurement error that occurs during the measurement of the mark positions. The values of the calibration parameters are determined based on the model with consideration of the measured mark positions.

Abstract: The position of an edge of a marker structure in an image of the marker structure is determined with subpixel accuracy. A discrete intensity profile of the edge, having profile pixels, is derived from the image pixels, and a continuous profile function of the edge is determined based on the profile pixels. Profile pixels whose intensity values are near an intensity threshold value are selected as evaluation pixels. Based on the evaluation pixels, a curve of continuous intensity is calculated. A position coordinate at which the intensity value of the continuous intensity curve matches the threshold value is selected as a first position coordinate, and the distance is determined between the first position coordinate and the position coordinate of the evaluation pixel that, from among the evaluation pixels previously selected, has the closest intensity value to the threshold value.

Abstract: The invention relates to a method for determining a performance of a photolithographic mask at an exposure wavelength with the steps of scanning at least one electron beam across at least one portion of the photolithographic mask, measuring signals generated by the at least one electron beam interacting with the at least one portion of the photolithographic mask, and determining the performance of the at least one portion of the photolithographic mask at the exposure wavelength based on the measured signals.