A laser annealing method performed on a reflective photomask may include preparing a reflective photomask including a pattern area and a border area surrounding the pattern area and irradiating a laser beam onto the border area of the reflective photomask. The irradiating of the laser beam may include split-irradiating a plurality of laser beam spots onto the border area. Each of the plurality of laser beam spots may be shaped using a beam shaper. The beam shaper may include a blind area, a transparent area at a center of the blind area, and a semitransparent area between the blind area and the transparent area. Each of the plurality of laser beam spots may include a center portion passing through the transparent area and having a uniform energy profile and an edge portion passing through the semitransparent area and having an inclined energy profile.

A reflective mask includes a substrate, a reflective multilayer disposed over the substrate, a capping layer disposed over the reflective multilayer, an intermediate layer disposed over the capping layer, an absorber layer disposed over the intermediate layer, and a cover layer disposed over the absorber layer. The intermediate layer includes a material having a lower hydrogen diffusivity than a material of the capping layer.

A reflective mask includes a substrate, a reflective multilayer disposed over the substrate, a capping layer disposed over the reflective multilayer, an intermediate layer disposed over the capping layer, an absorber layer disposed over the intermediate layer, and a cover layer disposed over the absorber layer. The intermediate layer includes a material having a lower hydrogen diffusivity than a material of the capping layer.

Fabricating a photomask includes forming a protection layer over a substrate. A plurality of multilayers of reflecting films are formed over the protection layer. A capping layer is formed over the plurality of multilayers. An absorption layer is formed over capping layer. A first photoresist layer is formed over portions of absorption layer. Portions of the first photoresist layer and absorption layer are patterned, forming first openings in absorption layer. The first openings expose portions of the capping layer. Remaining portions of first photoresist layer are removed and a second photoresist layer is formed over portions of absorption layer. The second photoresist layer covers at least the first openings. Portions of the absorption layer and capping layer and plurality of multilayer of reflecting films not covered by the second photoresist layer are patterned, forming second openings. The second openings expose portions of protection layer and second photoresist layer is removed.

A method for cleaning a substrate is provided. The method includes following operations. A substrate is received. The substrate has a plurality of conductive nanoparticles disposed over a surface of the substrate. A first mixture is applied to remove the conductive nanoparticles. The first mixture includes an SC1 solution, DI water and O.sub.3. A second mixture is applied to the photomask substrate. The second mixture includes DI wafer and H.sub.2. A temperature of the second mixture is between approximately 20° C. and 40° C. The applying of the second mixture further includes a mega sonic agitation, and a frequency of the mega sonic agitation is greater than 3 MHz. A flow rate of the first mixture is between approximately 1000 ml/min and approximately 5000 ml/min. A flow rate of the second mixture is between 1000 ml/min and approximately 3000 ml/min.

A method to improve a lithographic process for imaging a portion of a patterning device pattern onto a substrate using a lithographic projection having an illumination system and projection optics, the method including: (1) obtaining a simulation model that models projection of radiation by the projection optics, wherein the simulation model models an effect of an obscuration in the projection optics, and configuring, based on the model, the portion of the patterning device pattern, and/or (2) obtaining a simulation model that models projection of radiation by the projection optics, wherein the simulation model models an anamorphic demagnification of radiation by the projection optics, and configuring, based on the model, the portion of the patterning device pattern taking into account an anamorphic manufacturing rule or anamorphic manufacturing rule ratio.

A method to improve a lithographic process for imaging a portion of a patterning device pattern onto a substrate using a lithographic projection having an illumination system and projection optics, the method including: (1) obtaining a simulation model that models projection of radiation by the projection optics, wherein the simulation model models an effect of an obscuration in the projection optics, and configuring, based on the model, the portion of the patterning device pattern, and/or (2) obtaining a simulation model that models projection of radiation by the projection optics, wherein the simulation model models an anamorphic demagnification of radiation by the projection optics, and configuring, based on the model, the portion of the patterning device pattern taking into account an anamorphic manufacturing rule or anamorphic manufacturing rule ratio.

A reflective film coated substrate includes a substrate having two main surfaces opposite to each other and end faces connected to outer edges of the two main surfaces; and a reflective film formed on one of the main surfaces and extending onto at least part of the end faces. The reflective film on the main surface has a multilayer structure including low refractive index layers and high refractive index layers alternately formed. The reflective film which extends onto the end faces has a single-layer structure containing a first element higher in content than any other element in the low refractive index layers and a second element higher in content than any other element in the high refractive index layers.

A reflective film coated substrate includes a substrate having two main surfaces opposite to each other and end faces connected to outer edges of the two main surfaces; and a reflective film formed on one of the main surfaces and extending onto at least part of the end faces. The reflective film on the main surface has a multilayer structure including low refractive index layers and high refractive index layers alternately formed. The reflective film which extends onto the end faces has a single-layer structure containing a first element higher in content than any other element in the low refractive index layers and a second element higher in content than any other element in the high refractive index layers.

A reflective mask includes a substrate, a reflective multilayer disposed over the substrate, a capping layer disposed over the reflective multilayer, an intermediate layer disposed over the capping layer, an absorber layer disposed over the intermediate layer, and a cover layer disposed over the absorber layer. The absorber layer includes one or more layers of an Ir based material, a Pt based material or a Ru based material.