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 method of fabricating a photomask includes depositing a phase shifter over a light transmitting substrate, depositing a shading layer over the light transmitting substrate, and removing a portion of the shading layer and a portion of the phase shifter to expose a portion of the light transmitting substrate. The phase shifter having at least two semiconductor layers and at least two dielectric layers.

In a halftone phase shift mask blank comprising a transparent substrate and a halftone phase shift film thereon, the halftone phase shift film is composed of a silicon base material consisting of silicon, nitrogen and 0-6 at % of oxygen, has a refractive index n of at least 2.4, an extinction coefficient k of 0.4-0.7, and a thickness of 40-67 nm. The halftone phase shift film is thin enough to be advantageous for photomask pattern formation, has chemical resistance against chemical cleaning, and maintains a necessary phase shift for phase shift function and a necessary transmittance for halftone function.

A photomask includes a light transmission substrate, a plurality of pattern regions disposed over the light transmission substrate, a shape of the plurality of pattern regions being transferred onto a wafer during an exposure process, and a light blocking region surrounding the plurality of pattern regions. Each of the plurality of pattern regions is a light transmitting region that exposes a portion of the light transmission substrate. The light blocking region includes first light blocking patterns that respectively surround the plurality of pattern regions to have closed loop shapes and second light blocking patterns that are disposed between adjacent first light blocking patterns, adjacent second light blocking patterns being spaced apart from each other by a first distance in a first direction. And the first light blocking patterns have a first thickness and the second light blocking patterns have a second thickness which is smaller than the first thickness.

According to one embodiment, a mask includes a substrate, first and second pattern portions. The substrate includes a first surface, and the substrate is light transmissive. The first pattern portion includes first optical members. The first optical members are provided on the first surface. A light transmittance of the first optical members is lower than a light transmittance of the substrate. A distance between the adjacent two first optical members is a first distance. The second pattern portion includes second optical members. The second optical members are provided on the first surface. A light transmittance of the second optical members is lower than the light transmittance of the substrate. A distance between the adjacent two second optical members is a second distance. A first phase of a light penetrating the first pattern portion is different from a second phase of a light penetrating the second pattern portion.

A mask is disclosed which includes a plurality of first phase shift regions disposed on a first side of the mask, and a plurality of second phase shift regions disposed on a second side of the mask. The first phase shift regions and second phase shift regions may be alternating phase shift regions in which phase shift of the first phase shift regions is out of phase, for instance by 180 degrees, from phase shift of the second phase shift regions. A method for forming the mask, and a semiconductor device fabrication method using the mask is also disclosed.

A mask is disclosed which includes a plurality of first phase shift regions disposed on a first side of the mask, and a plurality of second phase shift regions disposed on a second side of the mask. The first phase shift regions and second phase shift regions may be alternating phase shift regions in which phase shift of the first phase shift regions is out of phase, for instance by 180 degrees, from phase shift of the second phase shift regions. A method for forming the mask, and a semiconductor device fabrication method using the mask is also disclosed.

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 photomask blank including a transparent substrate, a film composed of a material containing chromium, and a film composed of a material containing tantalum is provided. The film composed of a material containing tantalum is constituted of a single layer or multiple layers, and has a thickness of 0.5 to 15 nm; the material containing tantalum contains tantalum, and oxygen or oxygen and nitrogen, and is free of silicon; the single layer and at least the layer remotest from the transparent substrate among the layers constituting the multiple layers are composed of a material containing tantalum that has a tantalum content of 40 to 80 at %, an oxygen content of 5 to 50 at %, and a nitrogen content of not more than 50 at %; and the layer remotest from the transparent substrate has a thickness of not less than 0.5 nm.