A photo mask assembly including a photo mask, a first adhesive layer adhered with the photo mask, a pellicle frame and a pellicle is provided. The pellicle frame includes a plurality of recesses for accommodating the first adhesive layer. The pellicle frame is adhered with the photo mask through the first adhesive layer accommodated in the plurality of recesses. The pellicle is disposed on the pellicle frame. The pellicle frame is between the pellicle and the first adhesive layer. An optical apparatus including the above-mentioned photo mask assembly is also provided.

A photo mask assembly including a photo mask, a first adhesive layer adhered with the photo mask, a pellicle frame and a pellicle is provided. The pellicle frame includes a plurality of recesses for accommodating the first adhesive layer. The pellicle frame is adhered with the photo mask through the first adhesive layer accommodated in the plurality of recesses. The pellicle is disposed on the pellicle frame. The pellicle frame is between the pellicle and the first adhesive layer. An optical apparatus including the above-mentioned photo mask assembly is also provided.

Provided is an adhesive removing device for removing an adhesive for adhering a mask and a pellicle from the mask. The adhesive removing device includes: a laser irradiating unit configured to irradiate a laser beam to an adhesive layer formed between the mask and the pellicle; a controller configured to control a wavelength, a waveform, and an energy density of the laser beam, so as to remove the adhesive layer through emission of the laser beam; and an imaging unit configured to monitor a region to which the laser beam is irradiated.

A structure including an EUV mask and a pellicle attached to the EUV mask. The pellicle includes a pellicle frame and a plurality of pellicle membrane layers attached to the pellicle frame. The plurality of pellicle membrane layers include at least one core pellicle membrane layer and an additional pellicle membrane layer is disposed on the at least one core pellicle membrane layer. In some embodiments, the additional pellicle membrane layer is a material having a thermal emissivity greater than 0.2, a transmittance greater than 80%, and a refractive index (n) for 13.5 nanometer source of greater than 0.9.

A structure including an EUV mask and a pellicle attached to the EUV mask. The pellicle includes a pellicle frame and a plurality of pellicle membrane layers attached to the pellicle frame. The plurality of pellicle membrane layers include at least one core pellicle membrane layer and an additional pellicle membrane layer is disposed on the at least one core pellicle membrane layer. In some embodiments, the additional pellicle membrane layer is a material having a thermal emissivity greater than 0.2, a transmittance greater than 80%, and a refractive index (n) for 13.5 nanometer source of greater than 0.9.

Provided is a pellicle for exposure to extreme ultraviolet light (EUVL) according to an example embodiment, and the pellicle includes a pellicle membrane; and a frame attached to the pellicle membrane, wherein the pellicle membrane includes a carbon-based main layer that has a first surface and a second surface, which are two surfaces opposite to each other; and a boron-based enhancement layer covering at least one surface selected from the first surface and the second surface. The pellicle according to an example embodiment may be used for an extended period of time in an extreme ultraviolet light exposure environment.

Provided is a pellicle for exposure to extreme ultraviolet light (EUVL) according to an example embodiment, and the pellicle includes a pellicle membrane; and a frame attached to the pellicle membrane, wherein the pellicle membrane includes a carbon-based main layer that has a first surface and a second surface, which are two surfaces opposite to each other; and a boron-based enhancement layer covering at least one surface selected from the first surface and the second surface. The pellicle according to an example embodiment may be used for an extended period of time in an extreme ultraviolet light exposure environment.

A pellicle including a water-soluble adhesive and a photomask assembly including the pellicle are provided. A pellicle may include a membrane, a pellicle frame, and a water-soluble adhesive disposed on the pellicle frame. The water-soluble adhesive may be prepared by a mixture including a water-soluble acrylic adhesive material in an amount of about 40% to about 55% by weight of the mixture, water or a solution of water and alcohol in an amount of about 40% to about 55% by weight of the mixture, and an additive in an amount of about 1% to about 5% by weight of the mixture.

A pellicle including a water-soluble adhesive and a photomask assembly including the pellicle are provided. A pellicle may include a membrane, a pellicle frame, and a water-soluble adhesive disposed on the pellicle frame. The water-soluble adhesive may be prepared by a mixture including a water-soluble acrylic adhesive material in an amount of about 40% to about 55% by weight of the mixture, water or a solution of water and alcohol in an amount of about 40% to about 55% by weight of the mixture, and an additive in an amount of about 1% to about 5% by weight of the mixture.

Disclosed is a pellicle including a pellicle membrane including a carbon-based membrane having a carbon content of 40% by mass or more and a support frame that supports the pellicle membrane, in which the pellicle membrane and the support frame are in contact with each other, and at least one of the following conditions 1 and 2 is satisfied. [Condition 1] In the support frame, a surface in contact with the pellicle membrane has a roughness Ra of 1.0 ?m or less. [Condition 2] The support frame has a width of unevenness of 10 ?m or less at an edge portion on a surface side in contact with the pellicle membrane and on an inner side of the pellicle.