Abstract: Methods for manufacturing a photomask, photomask blanks, and photomasks used in chip fabrication. A phase-shift layer is formed on a mask blank, a hardmask layer is formed on the phase-shift layer, and a layer stack is formed on the hardmask layer to make a photomask blank. The layer stack includes a first layer comprised of a first material and a second layer comprised of a second material that can be etched selective to the first material. The first layer is thicker than the second layer, and the first layer is also thicker than the hardmask layer. The photomask blank may be used to make a photomask in which, during manufacture, the hardmask layer is used to pattern mask features in a chip area of the photomask and the thicker of the first layer or the second layer is used to pattern a frame of the photomask.

Abstract: Methods for manufacturing a photomask, photomask blanks, and photomasks used in chip fabrication. A phase-shift layer is formed on a mask blank, a hardmask layer is formed on the phase-shift layer, and a layer stack is formed on the hardmask layer to make a photomask blank. The layer stack includes a first layer comprised of a first material and a second layer comprised of a second material that can be etched selective to the first material. The first layer is thicker than the second layer, and the first layer is also thicker than the hardmask layer. The photomask blank may be used to make a photomask in which, during manufacture, the hardmask layer is used to pattern mask features in a chip area of the photomask and the thicker of the first layer or the second layer is used to pattern a frame of the photomask.

Abstract: The present disclosure relates to lithographic masks and, more particularly, to a lithographic mask substrate structure and methods of manufacture. The mask includes a sub-resolution assist feature (SRAF) formed on a quartz substrate and composed of a patterned transition film and absorber layer.

Abstract: The present disclosure relates to lithographic masks and, more particularly, to a lithographic mask substrate structure and methods of manufacture. The mask includes a sub-resolution assist feature (SRAF) formed on a quartz substrate and composed of a patterned transition film and absorber layer.

Abstract: A method for adjusting the flatness of a lithographic mask includes determining an initial mask flatness of the mask, determining an applied stress for bringing the mask to a desired mask flatness, and determining a mounting temperature of a pellicle frame to be mounted to the mask, the mounting temperature corresponding to the applied stress. The actual temperature of the pellicle frame is adjusted to the determined mounting temperature.