Abstract: An apparatus for X-ray analysis comprises (1)a focusing optical system including an X-ray source, a specimen table and a two-dimensional X-ray detector, (2)a device for shifting the angle of incidence of X-rays relative to a specimen supported by the specimen table, (3)a device for moving the two-dimensional X-ray detector in parallel with a central axis of rotation of the specimen and (4)a mask arranged in front of the two-dimensional X-ray detector. The mask has a slit arranged on a line intersecting a plane rectangularly intersecting said central axis of rotation of the specimen and containing a central optical axis of incident X-rays. The mask having the slit is driven to move in parallel with the axis of rotation of the specimen so that a measuring operation can be conducted on the basis of the focusing method by using the two-dimensional X-ray detector.

Abstract: A solution for mitigating the effects of EUV substrate surface defects is disclosed. In one embodiment, a layer of polyimide material is formed upon a mask substrate surface, resulting in a substantially defect free surface adjacent to which a reflective multilayer may be positioned for EUV lithography. To reduce the possibility of polyimide outgassing and resultant added roughness to adjacently positioned layers, the layer of polyimide may be cured in a vacuum at an elevated temperature before other layers are adjacently positioned.

Abstract: Disclosed is an X-ray mask for use in an exposure apparatus for transferring a circuit pattern onto an exposure substrate by use of an X-ray beam to produce a semiconductor device, wherein the X-ray mask includes an X-ray transmission film having a layered X-ray absorptive material formed thereon, and a holding frame for holding the X-ray transmission film, and wherein the X-ray transmission film is held by the holding frame with an even step-like structure defined at its peripheral portion. With this arrangement, a dust particle adhered to the X-ray mask surface and having a predetermined height can be detected precisely, such that a large integration device can be produced effectively.

Abstract: A method of inspecting a photomask for a semiconductor integrated circuit formed based on drawing pattern data, includes the steps of classifying a drawing pattern of the semiconductor integrated circuit into a plurality of ranks in accordance with a predetermined reference and extracting the same, determining inspecting accuracy for each of the ranks, and deciding quality of the photomask depending on whether the determined inspecting accuracy is satisfied.

Abstract: The present invention describes a method for fabricating an x-ray mask tool which is a contact lithographic mask which can provide an x-ray exposure dose which is adjustable from point-to-point. The tool is useful in the preparation of LIGA plating molds made from PMMA, or similar materials. In particular the tool is useful for providing an ability to apply a graded, or “stepped” x-ray exposure dose across a photosensitive substrate. By controlling the x-ray radiation dose from point-to-point, it is possible to control the development process for removing exposed portions of the substrate; adjusting it such that each of these portions develops at a more or less uniformly rate regardless of feature size or feature density distribution.

Abstract: A reflective mask may include an anti-reflective (AR) coating on an absorber layer to improve inspection contrast in an inspection system using deep ultraviolet (DUV) light. A silicon nitride (Si3N4) AR coating may be used on a chromium (Cr) or tantalum nitride (TaN) absorber layer.

Abstract: A trough adjusted optical proximity correction for vias which takes into account the topography on a wafer created by prior processing. The vias are classified into one of two groups, coincident vias which have an edge coincident with an edge of the trough, and noncoincident vias which do not have an edge coincident with an edge of the trough, by analyzing the via and trough designs. Any coincident via is marked as valid for an optical proximity correction (OPC). Any noncoincident via is marked invalid for OPC. OPC is then performed to the via level. Only vias marked as valid for OPC will keep the correction. All other vias will keep their original design size. Alternatively, coincident vias can be simply treated differently from noncoincident vias. For instance, coincident vias can be subjected to an aggressive OPC correction, while noncoincident vias are subjected to a less aggressive OPC correction.

Abstract: An X-ray mask has a mask pattern, a protection means for forming a dust-proof space for protecting the mask pattern, and an inner atmospheric pressure adjustment hole for ventilating between the dust-proof space and the outer atmosphere. The X-ray mask can be either a transmission type mask in which the mask pattern is formed on a membrane, or a reflection type mask in which a multilayered film reflection layer and the mask pattern are formed on a substrate.

Abstract: An extreme ultraviolet light (EUV) mask structure and method are disclosed to address the structural and processing requirements of EUV lithography. A mask absorber layer anisotropically etched with minimal etch bias at a relatively fast etch rate, is combined with a thin ruthenium layer, to produce a mask obviating the need for a conventional buffer or cap layer.

Abstract: Damage-resistant coatings are provided on radiation-exposed surfaces of EUV lithographic components. The diamond coating provides resistance to particle impingement, cleaning processes, and degradation due to high temperatures. The diamond coating is beneficial when deposited on the reflecting surface of an EUV Si/Mo multilayer mirror, the reflecting surface of an EUV Si/Mo multilayer reflective mask, and radiation-exposed surfaces of EUV debris shield. The diamond coating provides longer lasting EUV components.

Abstract: The present invention relates to the preparation of an x-ray photomask by exposing a free-standing film of a radiation sensitive metal/chalcogenide to an electron beam scanned in a defined pattern so as to generate areas in the film of reduced metal content in accordance with the defined pattern, as well as novel x-ray photomasks.

Abstract: A lithographic projection apparatus is provided with an electrostatic chuck. The electrostatic chuck includes a dielectric element which has a plurality of pins formed on a first surface. The item to be clamped is clamped in position on the chuck by applying a potential difference between an electrode located on the surface of the dielectric member opposite to the clamping surface and an electrode located on the clamping surface of the item to be clamped. The pins are provided with at least an upper conducting layer, which serves to reduce the Johnsen-Rahbek effect, allowing the substrate to be released more quickly.

Abstract: A reticle holder 18 has; a first suction section 63 facing a precision warrantable area AR1 having a predetermined surface precision, of a lower face Ra of a reticle R; a second suction section 64 facing a precision unwarrantable area AR2 outside of the precision warrantable area AR1; a pore 70a connected to a suction apparatus which draws out gas in a space between the lower face Ra of the reticle R and the first suction section 63, and a pore 70b connected to the suction apparatus 72 which draws out gas in the space between the lower face Ra of the reticle R and the second suction section 64. As a result, the reticle can be held stably, without deteriorating the surface precision of the precision warrantable area.

Abstract: An EUV mask (10) includes an opening (26) that helps to attenuate and phase shift extreme ultraviolet radiation using a subtractive rather than additive method. An etch stop layer (20) may be provided between a lower multilayer reflective stack (14) and an upper multilayer reflective stack (22) to ensure an appropriate and accurate depth of the opening. An absorber layer (32) may be deposited within the opening to sufficiently reduce the amount of reflection within dark region (30). Optimal thicknesses and locations of the various layers are described.

Abstract: A photoresist layer on a substrate wafer is exposed in first sections with a first exposure radiation and in second sections with a second exposure radiation that is phase-shifted by 180°. The first and second sections adjoin one another in boundary regions in which the photoresist layer is artificially not sufficiently exposed. Where a distance between these boundary regions is smaller than a photolithographically critical, least distance, the photoresist layer is exposed, at a first boundary region, with a third exposure radiation and at a second boundary region with a fourth exposure radiation phase-shifted by 180°. A trim mask provided for the process has a first translucent region and a second translucent region. The first light-transparent region and the second light-transparent region are fashioned such that the light passing through the first light-transparent region and the light passing through the second light-transparent region has a phase displacement of 180°.

Abstract: An exposure method for transferring a pattern of a mask onto a member to be exposed. The method includes the steps of making preparations for exposure while a protection cover is attached to the mask, executing alignment between the member to be exposed and the mask while the protection cover is detached from the mask, and executing exposure with X-rays while the protection cover is detached from the mask.

Abstract: A method for the elimination of high-energy ion in an EUV light-radiating device includes irradiating a first target with a first exciting laser to produce a laser-produced plasma EUV light source and causing a high-energy ion generated simultaneously with EUV light to collide against plasma produced by irradiating a second target with a second laser to separate the high-energy ion from the orbit of the EUV light. An apparatus for the elimination of a high-energy ion in an EUV light-radiating device includes a device for irradiating a first target with a first exciting laser to produce a plasma EUV light source and induce emission of EUV light, a device for irradiating a second target with a second laser to produce plasma, and a device for causing a high-energy ion generated simultaneously with the EUV light to be delayed by difference between an ion flight time and plasma expansion time for ion elimination and collide against the plasma to separate the high-energy ion from the orbit of the EUV light.

Abstract: A reflection-type mask for use in exposing a pattern onto a photosensitive material, wherein the mask includes a reflection area, having a multilayer film, for reflecting exposure light, and a non-reflection area which does not reflect the exposure light, the reflection area and the non-reflection area forming a mask pattern, wherein at least one layer of the multilayer film consists of an impurity semiconducter, whereby bad influences, for example, caused by poor conduction of the multilayer film at mask-production stage, can be prevented.

Abstract: Electron beam (e-beam) shot linearity monitoring is disclosed. A pattern is written that has a predetermined size and a predetermined form in a predetermined position on a substrate, such as a semiconductor wafer, a reticle, or a photomask. The pattern writing fixes the e-beam shot size, as located along one or more critical dimensions of the pattern. The critical dimensions are then measured, where their variations reflect the e-beam shot size linearity. Thereafter, deficiencies in the e-beam shot size linearity can be compensated for, to allow for properly produced semiconductor patterns.

Abstract: A lithographic projection apparatus includes a radiation system for providing a projection beam of radiation having a wavelength &lgr;1 smaller than 50 nm; a support structure for supporting patterning structure, the patterning structure serving to pattern the projection beam according to a desired pattern; a substrate table for holding a substrate; and a projection system for projecting the patterned beam onto a target portion of the substrate. The apparatus further includes a radiation sensor which is located so as to be able to receive radiation out of the projection beam, said sensor comprising a radiation-sensitive material which converts incident radiation of wavelength &lgr;1 into secondary radiation; and sensing means capable of detecting said secondary radiation emerging from said layer.

Abstract: Reflective reticles are disclosed that exhibit reduced internal stress and that are capable of being electrostatically chucked to a reticle stage, even if the reticle substrate is made from low-expansion (LE) glass, LE-ceramic, or analogous reticle substrate. If the reticle is made from LE-glass, for example, the reticle includes a conductive layer formed on the surface of the reticle normally contacting the reticle chuck. Another LE material that can be used is “Super Invar,” which is conductive and does not require a conductive layer per se, but desirably includes a conductive “flattening layer.” Internal stress in the reticle is reduced by using a LE reticle substrate and by controlling the thickness and “stress code” of the conductive and/or flattening layers.

Abstract: A pattern region of a working reticle is divided into existing pattern portions and newly-forming pattern portions. With respect to the existing pattern portions, already-formed master reticle patterns are reduction-projected while stitching screens using an optical-type projection exposure apparatus. With respect to the newly-forming portions, enlarged patterns are formed by an electron beam drawing apparatus to form new master reticles, and reduced images of the newly formed master reticles are exposed while stitching screens using an optical-type projection exposure apparatus.

Abstract: A method and apparatus for clamping a semiconductor mask to a carrier device is taught. The apparatus is comprised of a base member to which is attached an elongated spring. Both the base and the spring have affixed to them a means for compressively contacting the mask surface when the mask is put in place. In the preferred embodiment, that contact means is made of sapphire shaped in the form of a dome. The clamp further includes an adjustment screw that can be used to adjust the height of the contact means affixed to the base member. In this manner, the surface of the mask can be adjusted so that it is planarized to the right orientation relative to an e-Beam or laser source that will be used to scribe a pattern on the mask. Finally, the clamp includes electrical contacts, and the materials out of which the clamp is made are deliberately selected, so that no electrical or magnetic forces can build up on the clamp or the wafer that might adversely affect the scribing process.

Abstract: An EUV-transparent interface structure for optically linking a first closed chamber (80) and a second closed chamber (70) whilst preventing a contaminating flow of a medium and/or particles from one chamber to the other comprises an EUV-transparent member (60) in the form of a membrane (60) or a channel structure (100). An EUV-transparent (inert) gas (68) is forced to flow at the side of the member facing the source of contamination (LA; W) and towards the source of contamination to keep the contaminating particles away from the member (60; 100). The interface structure may be arranged between an EUV radiation source (LA) and the illuminator optics (IL) and/or between the projection system (PL) and the resist layer (RL) on top of a substrate (W) in a lithographic projection apparatus.

Abstract: A photolithographic mask for patterning a photosensitive material, in particular on a wafer, has at least one structure region for imaging a structure on the photosensitive material, and an absorber structure for absorbing incident radiation. At least one structure region is provided and has at least one protective layer made of chemically and mechanically resistive material. In this way, the photolithographic mask can be cleaned chemically and/or mechanically, without the structure regions being attacked and damaged by the chemical and/or mechanical cleaning media. Furthermore, a plurality of methods are possible for fabricating a photolithographic mask of this type.

Abstract: The present invention discloses an EUV mask having an improved absorber layer with a certain thickness that is formed from a metal and a nonmetal in which the ratio of the metal to the nonmetal changes through the thickness of the improved absorber layer and a method of forming such an EUV mask.

Abstract: The present invention relates to a test structure which is formed on a reticle simultaneously with a pattern that will be used to build an integrated circuit device. The test structure comprises a large rectangular end and several rectangular shapes that extend from one side of the rectangular end in a parallel array. The width of the rectangular shape extensions is equal to the spacing between them and is the same as the width of the minimum feature size in the lithographic process to be monitored. A CD SEM is used to measure the edge width of the convex and concave sections of the structure as printed in photoresist at various focus settings and a plot of edge width vs. focus setting is generated. The intersection of the lines representing the convex section and concave section measurements indicates the best focus setting for the lithographic process.

Abstract: Multilayer-film mirrors are disclosed that exhibit high reflectivity to incident X-radiation independently of the angle of incidence and without significantly compromising optical performance. Also disclosed are X-ray optical systems and microlithography apparatus comprising such mirrors. In an embodiment a multilayer-film mirror is formed by alternately laminating Mo layers (a material in which the difference between its refractive index in the weak X-ray band and its refractive index in a vacuum is great) and Si layers (a material in which said difference is small) on a substrate. The ratio (&Ggr;) of the thickness of the Mo layer to the total of the thickness of the Mo layer and the thickness of the Si layer has a distribution based on the distribution of angles of incidence of X-radiation on the mirror surface.

Abstract: The resolution achieved with a proximity printing method and apparatus can be increased considerably by using, instead of a photo mask, a diffraction mask (30) wherein the image information is encoded in a two-dimensional array (32) of image cells (37) having dimensions which are smaller than the minimum feature size to be printed, each image cell having one out of at least two amplitude levels and one out of at least three phase levels. The mask may be a multiple focus mask which has multiple focal planes within one image field.

Abstract: An object of the present invention is to accurately verify errors, etc., in programs when corrections of mask data are carried out by the programs. In order to correct the mask data based on predetermined conditions, a method for mask data verification according to the present invention comprises the steps of preparing corrected mask data by using a plurality of programs each of which has a different algorithm, comparing each of corrected mask data which is prepared in the previous step and as a result of the comparison, if there are differences among the corrected mask data, extracting errors which cause problems as mask data from the differences.

Abstract: A method for improving the imaging performance in a photolithographic system having a pupil plane and using a phase shift mask. A portion of the pupil plane where a phase error portion of a light from the phase shift mask is located. An aperture is placed at the located portion of the pupil plane. Typically, the phase error portion of the light from the phase shift mask is a zero order portion of the light often referred to as “zero order leakage”. Blocking the zero order leakage significantly mitigates the variations in the intensity of the light that exposes photoresist that is above or below the nominal focal plane. This, in turn, reduces the variations in the linewidths formed on the wafer.

Abstract: In the x-ray absorber in accordance with the present invention, reduced transmittance of the x-ray absorber is suppressed while the phase shift amount is provided in the vicinity of −&pgr; radian. For this purpose, it is characterized in that such a material is used that has a high transmittance per film thickness and contains an element with a high phase shift amount and an element with a low transmittance, as a material composition that forms the x-ray absorber. In other words, the transmittance of the x-ray absorber is mainly determined by the element with a low transmittance, and the phase shift amount falling short of −&pgr; radian is compensated with the element with a high transmittance and a high phase shift amount.

Abstract: In a pattern exposure method and apparatus for projecting a circuit pattern on a circuit member by an electron beam passing through a pattern exposure mask having a number of exposure regions separated from one another by a boundary region, the pattern exposure mask additionally includes a beam restraining area for restraining the electron beam scattered by the boundary region, so that the strength of the total background exposure is equalized.

Abstract: The present invention describes a method for fabricating an embossing tool or an x-ray mask tool, providing microstructures that smoothly vary in height from point-to-point in etched substrates, i.e., structure which can vary in all three dimensions. The process uses a lithographic technique to transfer an image pattern in the surface of a silicon wafer by exposing and developing the resist and then etching the silicon substrate. Importantly, the photoresist is variably exposed so that when developed some of the resist layer remains. The remaining undeveloped resist acts as an etchant barrier to the reactive plasma used to etch the silicon substrate and therefore provides the ability etch structures of variable depths.

Abstract: A method and structure for determining a range and a shape of a kernel function of a lithographic system which includes exposing, in the lithographic system, a photosensitive layer on a top surface of a substrate through a mask having a mask image, the mask image being of sufficient width to ensure a transferred image will not exhibit foreshortening but will exhibit corner rounding; developing the photosensitive layer to form the transferred image in the photosensitive layer; measuring a distance from an intersection of projected extensions of edges of the transferred image to a point along one edge where corner rounding starts; and defining the range of the kernel function as the measured distance. The projected extension edges are an unaltered version of the mask image overlaid on the transferred image and the foreshortening is a reduction in length of transferred images when compared to the mask image. Corner rounding occurs as a result of light diffraction and photosensitive layer development processes.

Abstract: An exposure method for exposing a workpiece in a proximity exposure system, includes a first exposure step for printing, by exposure, an image of a first mask pattern on a predetermined portion of the workpiece, and a second exposure step for printing, by exposure, an image of a second mask pattern, different from the first mask pattern, on the predetermined portion of the workpiece, wherein exposures in the first and second exposure steps are performed superposedly, prior to a development process.

Abstract: A method for manufacturing a pair of complementary masks for use in an electron projection lithographic (EPL) technique uses an algorithm for distributing the design data to a pair of EPL masks. The algorithm allocates a positive sign or negative sign to each of the pattern data, summation of the areas of the pattern data having positive signs while subtracting the areas of the pattern data having negative signs, for obtaining a minimum of the sum. One or more of initial combination of the signs is prepared and the vicinity of the initial combination is calculated therefrom for obtaining an optimum combination.

Abstract: A fine (short-stroke) stage is mounted on an XY slider and is capable of being moved over a minute range in the XY directions. Though the XY slider is moved along the X direction by a Y guide bar, movement along the X direction is decided by an X guide bar. If the relative angle between the direction of the X guide bar and the surface of a bar mirror of the fine stage is represented by &agr;, then the X guide bar will be moved by &agr;x when the XY slider has been moved by x along the X direction by the Y guide bar. After the fine stage is thus positioned, the relative positional relationship between the fine stage and the XY slider is held constant.

Abstract: Methods and apparatus are disclosed for accurately measuring stresses in respective membrane regions of segmented mask blanks destined to be made into masks or reticles for use in microlithography. A mask blank is held to a securing plate, e.g., by electrostatic attraction. The mask blank is held such that the struts of the mask blank contact the surface of the securing plate. The securing plate defines an array of through holes that are aligned with individual subfields of the mask blank. A pressure differential is applied across the membrane via the through-holes, causing the membrane regions to bulge. While measuring the pressure, the magnitude of bulge of individual membrane regions is measured using a displacement-measuring device. From data concerning the magnitude of bulge, membrane stress and Young's modulus are determined.

Abstract: Absorber material used in conventional EUVL reticles is eliminated by introducing a direct modulation in the complex-valued reflectance of the multilayer. A spatially localized energy source such as a focused electron or ion beam directly writes a reticle pattern onto the reflective multilayer coating. Interdiffusion is activated within the film by an energy source that causes the multilayer period to contract in the exposed regions. The contraction is accurately determined by the energy dose. A controllable variation in the phase and amplitude of the reflected field in the reticle plane is produced by the spatial modulation of the multilayer period. This method for patterning an EUVL reticle has the advantages of (1) avoiding the process steps associated with depositing and patterning an absorber layer and (2) providing control of the phase and amplitude of the reflected field with high spatial resolution.

Abstract: The present invention relates to a method of producing a structure of etch-resistant polymer on a substrate. A layer of sterol capable of polymerizing to form this structure is first deposited on a face of the substrate. Then, a first region of the layer of sterol is exposed to an electron beam to locally polymerize this layer and form the structure of etch-resistant polymer. A second region of the layer of sterol that has not been exposed to the electron beam is removed to leave on the face of the substrate only the structure of etch-resistant polymer. Finally, a region of the face of the substrate not covered by the structure of etch-resistant polymer can be etched away, and the structure of etch-resistant polymer removed following this etching.

Abstract: A mask and method for contact hole exposure. First, a mask including a transparent substrate, a 180° phase shift layer installed on the transparent substrate to define a series of patterns having contact hole transparent areas with 0° phase, and at least one 0° phase opening installed in the phase shift layer between the adjacent contact hole transparent areas is provided. Then, an exposure is performed by transmitting a light source, such as deep ultraviolet (UV), extreme ultraviolet, or X-ray, through the mask, so as to eliminate high degree diffraction waves by the 0° phase opening.

Abstract: An apparatus for marking objects is disclosed. The apparatus comprises (a) a source device including a mother isotope for emitting daughter isotopes by radioactive decay; preferably (b) a positioning mechanism for positioning an object in close proximity to the source device; and (c) a patterning mechanism for restricting implantation of the daughter isotopes into a surface of the object, so as to create a detectable pattern of the daughter isotopes on the object.

Abstract: The stage apparatus has a movable stage structure body which holds a substrate plate to be processed and is movable on a base structure body. This stage apparatus comprises a receipt edge orifice disposed at least at a portion of a fluid path which is disposed at said stage structure body; and a feed edge orifice being detachably engageable with said receipt edge orifice at a predetermined position on a base structure body and providing or discharging a predetermined fluid to the receipt edge orifice during said engagement of said feed edge orifice with said receipt edge orifice.

Abstract: A mask includes an in-situ information storage mechanism on the mask, which stores mask pattern data that is supplied to a microlithographic tool (e.g., an optical stepper). The advantages of using the invention include immediate availability of pattern data of a particular mask to the microlithographic tool for improved integrated circuit productivity.

Abstract: The invention provides systems and a method for reducing pellicle distortion. One feature of the invention reduces distortion of a pellicle by providing an airtight mounting structure for coupling a pellicle to a mask; and a port on the mounting structure though which a pressure difference can be created between the interior portion and an exterior environment. Hence, distortion can be reduced by controlling the pressure in the interior portion between the pellicle, the pellicle mounting structure and the mask. Another feature places an aerodynamic fairing adjacent the mask to reduce aerodynamic drag and, hence, suppress turbulent air flow over the pellicle. The features can be used separately or in combination.

Abstract: In an exposing method reflecting synchrotron radiation, having a critical wavelength of 8.46 Å, emitted from a radiation generator (SR device) having a deflecting magnetic field of 4.5 T and electron acceleration energy of 0.7 GeV twice through rhodium mirrors having an oblique-incidence angle of 1°, transmitting the light through a beryllium window of 20 &mgr;m and through an X-ray mask prepared by forming an X-ray absorber pattern on a diamond mask substrate of 2 &mgr;m in thickness and thereafter irradiating a resist surface provided on a substrate with the light, the resist has a main absorption waveband in the wave range of at least 3 Å and not more than 13 Å and contains an element generating Auger electrons having energy in the range of at least about 0.51 KeV and not more than 2.6 KeV upon exposure.

Abstract: An X-ray mask structure for use in X-ray lithography includes an X-ray transmission film to be disposed opposed to a workpiece in X-ray exposure, the X-ray transmission film having an X-ray absorptive material corresponding to a pattern to be printed on the workpiece, and a thin film covering at least a portion of the X-ray transmission film, the thin film having an anti-reflection function with respect to alignment light to be projected to the thin film for direct or indirect detection of relative positional deviation between the mask structure and the workpiece.

Abstract: A marking apparatus for forming alignment marks, which improves the alignment accuracy of each layer in the production of multi-layered printed circuit boards. An X-ray generator 11 irradiates X-rays at a standard mark 50 in a core board 51 of a board 5, and projects the image of the standard mark 50 on a fluorescence screen 12. The image is captured by a visible light CCD camera 13, thereby the position of the standard mark 50 is detected. Using the detected position of the standard mark 50 as an alignment reference, the apparatus irradiates ultra-violet rays at dry film resist layers 55 via mirrors 22 and 23, and imprints the marks emerged on photo masks 24 and 25 on the dry film resist layers 55, respectively.

Abstract: A reflective mask or reticle configured to reduce reflections from an absorptive layer during lithography at a wavelength shorter than in a deep ultraviolet (DUV) range is disclosed herein. The reflective mask or reticle is configured to generate additional reflections which have a desirable phase difference with respect to the reflections from the absorptive layer. The additional reflections reduce or eliminate the reflections from the absorptive layer by destructive interference.