A method of forming a pattern includes: preparing a target substrate including a photoresist layer on a base substrate; aligning a phase shift mask to the target substrate, the phase shift mask including a mask substrate comparted into a first region including a first sub region and second sub regions at sides of the first sub region, and second regions at sides of the first region, the phase shift mask including a phase shift layer on the mask substrate corresponding to the first region; fully exposing the photoresist layer at the first sub region and the second regions by utilizing the phase shift mask; and removing the photoresist layer at the first sub region and the second regions to form first and second photoresist patterns corresponding to the second sub regions. Transmittance of the phase shift layer is selected to fully expose the photoresist layer in the first sub region.

A photomask includes a low thermal expansion material (LTEM) substrate, a patterned opaque layer over the LTEM substrate, and a patterned capping layer over the opaque layer. The patterned capping layer includes a transition metal material for suppressing haze growth, such as metal oxide, metal nitride, or metal oxynitride. The material in the capping layer reacts with a hydrogenic compound from a lithography environment to for an atomic level hydrogen passivation layer. The passivation layer has superior ability to suppress photo-induced haze defect growth on the photomask surface, to improve production cycle time and reduce the production cost.

A photomask includes a low thermal expansion material (LTEM) substrate, a patterned opaque layer over the LTEM substrate, and a patterned capping layer over the opaque layer. The patterned capping layer includes a transition metal material for suppressing haze growth, such as metal oxide, metal nitride, or metal oxynitride. The material in the capping layer reacts with a hydrogenic compound from a lithography environment to for an atomic level hydrogen passivation layer. The passivation layer has superior ability to suppress photo-induced haze defect growth on the photomask surface, to improve production cycle time and reduce the production cost.

A method of forming a pattern includes: preparing a target substrate including a photoresist layer on a base substrate; aligning a phase shift mask to the target substrate, the phase shift mask including a mask substrate comparted into a first region including a first sub region and second sub regions at sides of the first sub region, and second regions at sides of the first region, the phase shift mask including a phase shift layer on the mask substrate corresponding to the first region; fully exposing the photoresist layer at the first sub region and the second regions by utilizing the phase shift mask; and removing the photoresist layer at the first sub region and the second regions to form first and second photoresist patterns corresponding to the second sub regions. Transmittance of the phase shift layer is selected to fully expose the photoresist layer in the first sub region.

The present invention provides a halftone mask comprising an assist pattern and a manufacturing method of the halftone mask, which uses an ArF excimer laser as an exposing source, is used for a projection exposure by an off axis illumination, does not resolve the assist pattern while keeping the focal depth magnification effect as the assist pattern, and may form a transferred image having high contrast of a main pattern. A photomask is a photomask comprising the main pattern which is transferred to a transfer-target surface by the projection exposure and the assist pattern which is formed nearby the main pattern and not transferred, characterized in that the main pattern and the assist pattern are each constituted from a semi-transparent film made of the same material, a retardation of 180 is generated between the light transmitting through the main pattern and the light transmitting through a transparent region of a transparent substrate, and a predetermined retardation within the scope of 70 to 115 is generated between the light transmitting through the assist pattern and the light transmitting through the transparent region of the transparent substrate.

The present invention provides a halftone mask comprising an assist pattern and a manufacturing method of the halftone mask, which uses an ArF excimer laser as an exposing source, is used for a projection exposure by an off axis illumination, does not resolve the assist pattern while keeping the focal depth magnification effect as the assist pattern, and may form a transferred image having high contrast of a main pattern. A photomask is a photomask comprising the main pattern which is transferred to a transfer-target surface by the projection exposure and the assist pattern which is formed nearby the main pattern and not transferred, characterized in that the main pattern and the assist pattern are each constituted from a semi-transparent film made of the same material, a retardation of 180 is generated between the light transmitting through the main pattern and the light transmitting through a transparent region of a transparent substrate, and a predetermined retardation within the scope of 70 to 115 is generated between the light transmitting through the assist pattern and the light transmitting through the transparent region of the transparent substrate.

A mask blank having a structure in which, on a transparent substrate, a light shielding film and a hard mask film are laminated in the stated order from the transparent substrate side. The hard mask film is formed of a material containing at least one element selected from silicon and tantalum, and the light shielding film is formed of a material containing chromium. The mask blank has a structure of three layers wherein a lower layer, an intermediate layer, and an upper layer are laminated in the stated order from the transparent substrate side. The upper layer has a lowest content of chromium in the light shielding film, the intermediate layer has a highest content of chromium in the light shielding film. It contains at least one metallic element selected from indium, tin, and molybdenum.

A mask blank having a structure in which, on a transparent substrate, a light shielding film and a hard mask film are laminated in the stated order from the transparent substrate side. The hard mask film is formed of a material containing at least one element selected from silicon and tantalum, and the light shielding film is formed of a material containing chromium. The mask blank has a structure of three layers wherein a lower layer, an intermediate layer, and an upper layer are laminated in the stated order from the transparent substrate side. The upper layer has a lowest content of chromium in the light shielding film, the intermediate layer has a highest content of chromium in the light shielding film. It contains at least one metallic element selected from indium, tin, and molybdenum.

An extreme ultraviolet (EUV) mask comprises a substrate, a first reflective layer above a surface of the substrate, and a second reflective layer over the first reflective layer. The second reflective layer has various openings that define a first state and a second state. The first state includes the first reflective layer and is free of the second reflective layer. The second state includes both the first and second reflective layers. The first state has a first reflection coefficient and a first reflectivity. The second state has a second reflection coefficient and a second reflectivity. A phase difference between the first and second reflection coefficients is about 180 degrees.

A photomask blank comprising a transparent substrate and a chromium-containing film deposited thereon is provided. The chromium-containing film comprises at least one CrC compound layer comprising up to 50 at % of Cr, at least 25 at % of O and/or N, and at least 5 at % of C. From the blank, a photomask having a photomask pattern formed on the substrate is produced, the photomask being used in photolithography of forming a resist pattern with a line width of up to 0.1 m, using exposure light having a wavelength of up to 250 nm.