Photomask, method for producing the same, and method for forming pattern using the photomask

A photomask comprising on a transparent substrate:

• a semi-light-shielding portion having a light-shielding property with respect to exposure light:
• a light-transmitting portion surrounded by the semi-light-shielding portion and having a light-transmitting property with respect to exposure light:
• and
• a peripheral portion surrounded by the semi-light-shielding portion and positioned in a periphery of the light-transmitting portion,
• wherein the semi-light-shielding portion and the light-transmitting portion transmit the exposure light in a same phase,
• the peripheral portion transmits the exposure light in a phase opposite to that of the semi-light-shielding portion and the light-transmitting portion,
• a surface of the transparent substrate in a formation region for the light-transmitting portion is exposed,
• a semi-light-shielding film that has a transmittance allowing the exposure light to be transmitted partially and transmits the exposure light in a same phase to that of the light-transmitting portion is formed on the transparent substrate in the semi-light-shielding portion formation region, and
• the semi-light-shielding film with a reduced thickness is formed on the transparent substrate in a formation region for the peripheral portion, the thickness being such an extent that the exposure light is transmitted in a phase opposite to that of the light-transmitting portion.

A photomask comprising on a transparent substrate:

• a semi-light-shielding portion having a light-shielding property with respect to exposure light:
• a light-transmitting portion surrounded by the semi-light-shielding portion and having a light-transmitting property with respect to exposure light:
• and
• a peripheral portion surrounded by the semi-light-shielding portion and positioned in a periphery of the light-transmitting portion,
• wherein the semi-light-shielding portion and the light-transmitting portion transmit the exposure light in a same phase,
• the peripheral portion transmits the exposure light in a phase opposite to that of the semi-light-shielding portion and the light-transmitting portion,
• a surface of the transparent substrate in a formation region for the light-transmitting portion is exposed,
• a semi-light-shielding film that has a transmittance that allows the exposure light to be transmitted partially and transmits the exposure light in a same phase as that of the light-transmitting portion is formed on the transparent substrate in the semi-light-shielding portion, and
• the transparent substrate in a formation region for the peripheral portion is dug down such that a thickness thereof is such an extent that the exposure light is transmitted in a phase opposite to that of the light-transmitting portion.

A method for producing a photomask comprising:

• a semi-light-shielding portion having a light-shielding property with respect to exposure light:
• a light-transmitting portion surrounded by the semi-light-shielding portion and having a light-transmitting property with respect to exposure light:
• and
• a peripheral portion surrounded by the semi-light-shielding portion and positioned in a periphery of the light-transmitting portion on a transparent substrate,
• the method comprising:
• a first step of forming a first phase shift film that transmits the exposure light in a phase opposite to that of the light-transmitting portion on the transparent substrate, and
• a second step of forming a second phase shift film that transmits the exposure light in a phase opposite to that of the light-transmitting portion on the first phase shift film,
• a third step of removing the second phase shift film in a formation region for the light-transmitting portion and a formation region for the peripheral portion, and
• a fourth step of removing the first phase shift film in the light-transmitting portion formation region after the third step,
• wherein a multilayered structure of the first phase shift film and the second phase shift film formed on the transparent substrate in the semi-light-shielding portion formation region has a transmittance that allows the exposure light to be transmitted partially and transmits the exposure light in a same phase as that of the light-transmitting portion.

A method for producing a photomask comprising:

• a semi-light-shielding portion having a light-shielding property with respect to exposure light:
• a light-transmitting portion surrounded by the semi-light-shielding portion and having a light-transmitting property with respect to exposure light:
• and
• a peripheral portion surrounded by the semi-light-shielding portion and positioned in a periphery of the light-transmitting portion on a transparent substrate,
• the method comprising:
• a first step of forming a first phase shift film that transmits the exposure light in a phase opposite to that of the light-transmitting portion on the transparent substrate, and
• a second step of forming a second phase shift film that transmits the exposure light in a phase opposite to that of the light-transmitting portion on the first phase shift film,
• a third step of removing the second phase shift film in a formation region for the peripheral portion, and
• a fourth step of removing the second phase shift film and the first phase shift film in the light-transmitting portion formation region sequentially after the third step,
• wherein a multilayered structure of the first phase shift film and the second phase shift film formed on the transparent substrate in the semi-light-shielding portion formation region has a transmittance that allows the exposure light to be transmitted partially and transmits the exposure light in a same phase as that of the light-transmitting portion.