Photomask blank and making method, photomask, light pattern exposure method, and design method of transition metal/silicon base material film

In connection with a photomask having formed thereon a pattern of a transition metal/silicon base material film of a material comprising a transition metal, silicon, oxygen and nitrogen,

• a method for designing the transition metal/silicon base material film such that the film pattern may be restrained in pattern line width variation degradation by irradiation of ArF excimer laser light, the method comprising the steps of:
• providing the transition metal/silicon base material film with an oxygen content of at least 3 atom %,
• constructing the transition metal/silicon base material film by a layer of a transition metal/silicon base material, a multilayer structure having at least two such layers stacked, or a combination of such a layer or a multilayer structure with a surface oxidized layer disposed remote from the substrate and having a thickness of up to 10 nm, and
• selecting a silicon content CSi and a transition metal content CM of the transition metal/silicon base material so as to satisfy the following formula (1):
• 4×CSi/100−6×CM/100>1 (1)
• wherein CSi is a silicon content in atom % and CM is a transition metal content in atom %.

In connection with a photomask having formed thereon a pattern of a transition metal/silicon base material film of a material comprising a transition metal, silicon, oxygen and nitrogen,

• a method for designing the transition metal/silicon base material film such that the film pattern may be restrained in pattern line width variation degradation by irradiation of ArF excimer laser light, the method comprising the steps of:
• providing the transition metal/silicon base material film with an oxygen content of at least 3 atom %,
• constructing the transition metal/silicon base material film by a layer of a transition metal/silicon base material, a multilayer structure having at least two such layers stacked, or a combination of such a layer or a multilayer structure with a surface oxidized layer disposed remote from the substrate and having a thickness of up to 10 nm, and
• selecting a silicon content CSi, a transition metal content CM, and a nitrogen content CN of the transition metal/silicon base material so as to satisfy the following formula (2):
• 4×CSi/100−6×CM/100−3×CN/100>−0.1 (2)
• wherein CSi is a silicon content in atom %, CM is a transition metal content in atom %, and CN is a nitrogen content in atom %.

In connection with a photomask having formed thereon a pattern of a transition metal/silicon base material film of a material comprising a transition metal, silicon, oxygen and nitrogen,

• a method for designing the transition metal/silicon base material film such that the film pattern may be restrained in pattern line width variation degradation by irradiation of ArF excimer laser light, the method comprising the steps of:
• providing the transition metal/silicon base material film with an oxygen content of at least 3 atom %,
• constructing the transition metal/silicon base material film by a layer of a transition metal/silicon base material, a multilayer structure having at least two such layers stacked, or a combination of such a layer or a multilayer structure with a surface oxidized layer disposed remote from the substrate and having a thickness of up to 10 nm, and
• selecting a silicon content CSi, a transition metal content CM, a nitrogen content CN, and an oxygen content CO of the transition metal/silicon base material so as to satisfy the following formula (3):
• 4×CSi/100−6×CM/100−3×CN/100+2×CO/100>0 (3)
• wherein CSi is a silicon content in atom %, CM is a transition metal content in atom %, CN is a nitrogen content in atom %, CO is an oxygen content in atom %.