A pellicle for an extreme ultraviolet (EUV) reflective mask includes a pellicle frame and a main membrane attached to the pellicle frame. The main membrane includes a plurality of nanotubes, each of which includes a single nanotube or a co-axial nanotube, and the single nanotube or an outermost nanotube of the co-axial nanotube is a non-carbon based nanotube.

A pellicle removal tool including a stage that holds a photomask and an associated pellicle, two or more arms positioned around the stage and configured to engage pellicle side wells of the pellicle, and two or more actuators each configured to adjust at least a vertical position of a corresponding one of the two or more arms so as to apply a lifting force to the pellicle for removal of the pellicle from the photomask.

A pellicle removal tool including a stage that holds a photomask and an associated pellicle, two or more arms positioned around the stage and configured to engage pellicle side wells of the pellicle, and two or more actuators each configured to adjust at least a vertical position of a corresponding one of the two or more arms so as to apply a lifting force to the pellicle for removal of the pellicle from the photomask.

A pellicle support frame is provided with a frame body made of aluminum alloy and has a pellicle film bonded to the upper surface of the frame body and a transparent substrate bonded to the lower surface of the frame body. Within the frame body, a plurality of hollow portions are provided to be lined up in the circumferential direction of the frame body, and a through-hole which leads from the outer peripheral surface to the inner peripheral surface of the frame body is formed between two adjacent hollow portions. This configuration makes it possible to prevent strain from arising in the support frame and the transparent substrate after the support frame is bonded to the transparent substrate.

A pellicle support frame is provided with a frame body made of aluminum alloy and has a pellicle film bonded to the upper surface of the frame body and a transparent substrate bonded to the lower surface of the frame body. Within the frame body, a plurality of hollow portions are provided to be lined up in the circumferential direction of the frame body, and a through-hole which leads from the outer peripheral surface to the inner peripheral surface of the frame body is formed between two adjacent hollow portions. This configuration makes it possible to prevent strain from arising in the support frame and the transparent substrate after the support frame is bonded to the transparent substrate.

There is provided a pellicle for lithography which has a unique frame in that it has externally protruding (projecting) portions; to the lower end faces of these protruding portions the photomask-bonding agglutinant layer is applied so as to allow a reduction in the area of the lower end face of the pellicle frame to which conventionally the agglutinant layer was endlessly applied, whereby the pellicle induced deformation to the photomask is mitigated.

There is provided a pellicle for lithography which has a unique frame in that it has externally protruding (projecting) portions; to the lower end faces of these protruding portions the photomask-bonding agglutinant layer is applied so as to allow a reduction in the area of the lower end face of the pellicle frame to which conventionally the agglutinant layer was endlessly applied, whereby the pellicle induced deformation to the photomask is mitigated.

A photomask assembly may be formed such that stress relief trenches are formed in a pellicle frame of the photomask assembly. The stress relief trenches may reduce or prevent damage to a pellicle that may otherwise result from deformation of the pellicle. The stress relief trenches may be formed in areas of the pellicle frame to allow the pellicle frame to deform with the pellicle, thereby reducing the amount damage to the pellicle caused by the pellicle frame.

A photomask assembly may be formed such that stress relief trenches are formed in a pellicle frame of the photomask assembly. The stress relief trenches may reduce or prevent damage to a pellicle that may otherwise result from deformation of the pellicle. The stress relief trenches may be formed in areas of the pellicle frame to allow the pellicle frame to deform with the pellicle, thereby reducing the amount damage to the pellicle caused by the pellicle frame.

A portion of a buffer layer on a backside of a substrate of a photomask assembly may be removed prior to formation of one or more capping layers on the backside of the substrate. The one or more capping layers may be formed directly on the backside of the substrate where the buffer layer is removed from the substrate, and a hard mask layer may be formed directly on the one or more capping layers. The one or more capping layers may include a low-stress material to promote adhesion between the one or more capping layers and the substrate, and to reduce and/or minimize peeling and delamination of the capping layer(s) from the substrate. This may reduce the likelihood of damage to the pellicle layer and/or other components of the photomask assembly and/or may increase the yield of an exposure process in which the photomask assembly is used.