US 6,639,732 B2 · Projection exposure apparatus and method

Abstract

The present invention relates to a projection exposure apparatus (10) for and method of imaging a reticle (R) having patterned surface onto a substrate (W) in photolithographic processes for manufacturing a variety of devices. The invention further relates to an optical system (C) having a folding member (M1) suited to the projection exposure apparatus, and a method for manufacturing the optical system. The projection exposure apparatus comprises an illumination optical system (IS) and a reticle stage (RS) capable of holding the reticle so the normal line to its patterned surface is in the direction of gravity. The apparatus also includes a substrate stage (WS) capable of holding the substrate with its surface normal parallel to the direction of gravity. The optical system includes a first imaging optical system (A) comprising a concave reflecting mirror and a dioptric optical member arranged along a first optical axis. The first imaging optical system (A) forms an intermediate image of the patterned surface. The optical system also includes a second imaging optical system (B) having a second optical axis, and forms a reduced image of the intermediate image on the substrate. The first folding member is arranged in the optical path from the first imaging optical system to the second imaging optical system. The first and second imaging optical systems and the first and second folding members are positioned so that a reduced image of the pattered surface is formed parallel to the pattern surface of the reticle, and the first and second optical axes are positioned so that they are substantially parallel to the direction of gravity.

Claims23

Dependent claims

A catadioptric projection optical system that makes first and second planes optically conjugate, the catadioptric projection optical system comprising:

a catadioptric imaging optical subsystem;
and
a refractive imaging optical subsystem;
wherein a position that is optically conjugate to the first and second planes is formed in an optical path between the catadioptric imaging optical subsystem and the refractive imaging optical subsystem;
the catadioptric imaging optical subsystem is arranged in the optical path between the first plane and the conjugate position;
the refractive imaging optical subsystem is arranged in an optical path between the second plane and the conjugate position;
and
the catadioptric imaging optical subsystem includes:
a concave reflecting surface;
at least one lens;
and
a first barrel that holds the concave reflecting surface and the at least one lens of the catadioptric imaging optical subsystem integrally,
the catadioptric projection optical system further comprising:
an optical path folding mirror arranged in an optical path between the concave reflecting surface and the refractive imaging optical subsystem;
and
a second barrel that holds the optical path folding mirror independently of the first barrel.

13 more elements

A catadioptric projection optical system including a plurality of lens surfaces and a plurality of reflecting surfaces, and that forms a reduced image of a first plane at a second plane, comprising:

a catadioptric imaging optical subsystem;
and
a refractive imaging optical subsystem;
wherein an intermediate image of the first plane is formed in an optical path between the catadioptric imaging optical subsystem and the refractive imaging optical subsystem,
the catadioptric imaging optical subsystem is arranged in an optical path between the first plane and a formation position of the intermediate image,
the refractive imaging optical subsystem is arranged in an optical path between the second plane and the intermediate image formation position,
the catadioptric imaging optical subsystem includes a concave reflecting surface,
the plurality of reflecting surfaces includes a first reflecting surface arranged in an optical path between the concave reflecting surface and the refractive imaging optical subsystem, and a second reflecting surface arranged in an optical path between the first plane and the refractive imaging optical subsystem,
the catadioptric optical system further comprising a first barrel that holds the first reflecting surface and the second reflecting surface integrally.

6 more elements

Dependencies are inferred from the claim text.

Projection exposure apparatus and method

Life of this patent

Projection exposure apparatus and method

Life of this patent

Abstract

Claims23