Projection optical system, exposure apparatus, and device manufacturing method

A projection optical system for performing reduction projection of a pattern of a reticle onto a projection plane, said system comprising:

• a first mirror having a concave reflective surface;
• a second mirror having a reflective surface;
• a third mirror having a convex reflective surface;
• a fourth mirror having a concave reflective surface;
• a fifth mirror having a convex reflective surface;
• and
• a sixth mirror having a concave reflective surface,
• wherein said first, second, third, fourth, fifth and sixth mirrors are disposed in the order named from the reticle,
• the reflective surface of said fourth mirror has a curvature radius of not less than 400 mm and not more than 800 mm in absolute value, and
• said projection optical system forms an intermediate image of the pattern between said fourth mirror and said fifth mirror.

A projection optical system for performing reduction projection of a pattern of a reticle onto a projection plane, said system comprising:

• a first mirror having a concave reflective surface;
• a second mirror having a convex reflective surface;
• a third mirror having a convex reflective surface;
• a fourth mirror having a concave reflective surface;
• a fifth mirror having a convex reflective surface;
• and
• a sixth mirror having a concave reflective surface,
• wherein said first, second, third, fourth, fifth and sixth mirrors are disposed in the order named from the reticle,
• the reflective surface of said sixth mirror has a curvature radius of not less than 400 mm and not more than 600 mm in absolute value, and
• said projection optical system forms an intermediate image of the pattern between said fourth mirror and said fifth mirror.

An exposure apparatus comprising:

• an illumination optical system for illuminating a pattern with light from a light source;
• and
• a projection optical system for projecting the pattern onto a member to be exposed at a reduced magnification;
• said projection optical system including:
• a first mirror having a concave reflecting surface;
• a second mirror having a reflective surface;
• a third mirror having a convex reflective surface;
• a fourth mirror having a concave reflecting surface;
• a fifth mirror having a convex reflective surface;
• and
• a sixth mirror having a concave reflective surface,
• wherein said first, second, third, fourth, fifth and sixth mirrors are disposed in the order named from the pattern,
• wherein said reflective surface of said fourth mirror has a curvature radius of not less than 400 mm and not more than 800 mm in absolute value,
• said reflective value of said sixth mirror has a curvature radius of not less than 400 mm and not more than 600 mm in absolute value,
• said reflective surfaces of said first, second, third, fourth, fifth and sixth mirrors have a curvature radius of not more than 1500 mm in absolute value, respectively, and
• said projection optical system forms an intermediate image of the pattern between said fourth mirror and said fifth mirror.

A device manufacturing method comprising:

• a step of exposing a member to be exposed using an exposure apparatus;
• and
• a step of developing the member having been exposed in said exposing step,
• wherein the exposure apparatus includes:
• an illumination optical system for illuminating a pattern with light from a light source;
• and
• a projection optical system for projecting the pattern onto the member at a reduced magnification,
• the projection optical system including:
• a first mirror having a concave reflective surface;
• a second mirror having a reflective surface;
• a third mirror having a convex reflective surface;
• a fourth mirror having a concave reflective surface;
• a fifth mirror having a convex reflective surface;
• and
• a sixth mirror having a concave reflective surface,
• wherein the first, second, third, fourth, fifth and sixth mirrors are disposed in the order named from the pattern,
• said reflective surface of said fourth mirror has a curvature radius of not less than 400 mm and not more than 800 mm in absolute value,
• the reflective surface of the sixth mirror has a curvature radius of not less than 400 mm and not more than 600 mm in absolute value,
• the reflective surfaces of the first, second, third, fourth, fifth and sixth mirrors have a curvature radius of not more than 1500 mm in absolute value, respectively, and
• said projection optical system forms an intermediate image of the pattern between said fourth mirror and said fifth mirror.

An exposure apparatus comprising:

• an illumination optical system for illuminating a pattern with light from a light source;
• and
• a projection optical system for projecting the pattern onto a member to be exposed at a reduced magnification,
• said projection optical system including:
• a first mirror having a concave reflective surface;
• a second mirror having a reflective surface;
• a third mirror having a convex reflective surface;
• a fourth mirror having a concave reflective surface;
• a fifth mirror having a convex reflective surface;
• and
• a sixth mirror having a concave reflective surface,
• wherein said first, second, third, fourth, fifth and sixth mirrors are disposed in the order named from the pattern,
• said reflective surface of said fourth mirror has a curvature radius of not less than 400 mm and not more than 800 mm in absolute value, and
• said projection optical system forms an intermediate image of the pattern between said fourth mirror and said fifth mirror.

A device manufacturing method comprising:

• a step of exposing a member to be exposed using an exposure apparatus;
• and
• a step of developing the member having been exposed in said exposing step,
• the exposure apparatus including:
• an illumination optical system for illuminating a pattern with light from a light source;
• and
• a projection optical system for projecting the pattern onto a member to be exposed at a reduced magnification,
• the projection optical system including:
• a first mirror having a concave reflective surface;
• a second mirror having a reflective surface;
• a third mirror having a convex reflective surface;
• a fourth mirror having a concave reflective surface;
• a fifth mirror having a convex reflective surface;
• and
• a sixth mirror having a concave reflective surface,
• wherein the first, second, third, fourth, fifth and sixth mirrors are disposed in the order named from the pattern,
• the reflective surface of the fourth mirror has a curvature radius of not less than 400 mm and not more than 800 mm in absolute value, and
• said projection optical system forms an intermediate image of the pattern between said fourth mirror and said fifth mirror.

An exposure apparatus comprising:

• an illumination optical system for illuminating a pattern with light from a light source;
• and
• a projection optical system for projecting the pattern onto a member to be exposed at a reduced magnification,
• said projection optical system including:
• a first mirror having a concave reflective surface;
• a second mirror having a reflective surface;
• a third mirror having a convex reflective surface;
• a fourth mirror having a concave reflective surface;
• a fifth mirror having a convex reflective surface;
• and
• a sixth mirror having a concave reflective surface,
• wherein said first, second, third, fourth, fifth and sixth mirrors are disposed in the order named from the pattern,
• said reflective surface of said sixth mirror has a curvature radius of not less than 400 mm and not more than 600 mm in absolute value, and
• said projection optical system forms an intermediate image of the pattern between said fourth mirror and said fifth mirror.

A device manufacturing method comprising:

• a step of exposing a member to be exposed using an exposure apparatus;
• and
• a step of developing the member having been exposed in said exposing step,
• the exposure apparatus including:
• an illumination optical system for illuminating a pattern with light from a light source;
• and
• a projection optical system for projecting the pattern onto a member to be exposed at a reduced magnification,
• the projection optical system including:
• a first mirror having a concave reflective surface;
• a second mirror having a reflective surface;
• a third mirror having a convex reflective surface;
• a fourth mirror having a concave reflective surface;
• a fifth mirror having a convex reflective surface;
• and
• a sixth mirror having a concave reflective surface;
• wherein the first, second, third, fourth, fifth and sixth mirrors are disposed in the order named from the pattern,
• the reflective surface of the sixth mirror has a curvature radius of not less than 400mm and not more than 600mm in absolute value, and
• said projection optical system forms an intermediate image of the pattern between said fourth mirror and said fifth mirror.