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

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 phase shift film that has a transmittance that allows the exposure light to be transmitted partially and transmits the exposure light in a phase opposite to that of the peripheral portion on the transparent substrate in the semi-light-shielding portion formation region, and
• a second step of digging down the transparent substrate in the light-transmitting portion formation region so as to have a thickness that transmits the exposure light in a phase opposite to that of the peripheral portion after the first step.

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 phase adjusting film that transmits the exposure light in a phase opposite to that of the peripheral portion and a transmittance adjusting film having a transmittance lower than that of the transparent substrate with respect to the exposure light sequentially on an entire surface of the transparent substrate,
• a second step of removing the phase adjusting film and the transmittance adjusting film in the peripheral portion formation region, and
• a third step of removing the transmittance adjusting film in the light-transmitting portion formation region after the second step,
• wherein the phase adjusting film and the transmittance adjusting film formed on the transparent substrate in the semi-light-shielding portion formation region constitute the phase shift film that has a transmittance that allows the exposure light to be transmitted partially and transmits the exposure light in a phase opposite to that of the peripheral portion.