Projection exposure apparatus

In a device manufacturing method, which includes a step of detecting through a detection optical system an imaging plane on which a device pattern is to be imaged by a projection optical system, a step of positioning a workpiece upon the detected imaging plane and a step of illuminating the device pattern with a beam from an illumination optical system such that an image of the device pattern is projected on the workpiece through the projection optical system, the improvement comprising the steps of:

• supplying to the detection optical system a shape of an effective light source, which is substantially the same as a shape of an effective light source of the illumination optical system;
• and
• illuminating, for the detection of the imaging plane, a mark with a beam from the detection optical system such that an image of the mark is projected through the projection optical system.

In a device manufacturing method, which includes a step of detecting through a detection optical system an imaging plane on which a device pattern is to be imaged by a projection optical system comprising a lens system, a step of positioning a workpiece upon the detected imaging plane and a step of illuminating the device pattern with an exposure beam from an illumination optical system such that an image of the device pattern is projected on the workpiece through the projection optical system, the improvement comprising the steps of:

• supplying to the detection optical system a shape of an effective light source, which is substantially the same as a shape of an effective light source of the illumination optical system;
• and
• illuminating, for the detection of the imaging plane, a mark with a detection beam from the detection optical system having substantially the same wavelength as that of the exposure beam, such that an image of the mark is projected through the projection optical system.

In a device manufacturing method which includes detecting through a detection optical system an imaging plane on which a device pattern is to be imaged by a projection optical system, positioning a workpiece upon the detected imaging plane and illuminating the device pattern with a beam from an illumination optical system such that an image of the device pattern is projected on the workpiece through the projection optical system, the improvements comprising the steps of:

• providing a shape of an effective light source to the detection optical system, wherein the shape of the effective light source is such that a light intensity on an optical axis of said detection optical system is lower than that at a peripheral portion around the optical axis;
• and
• illuminating, for detection of the imaging plane, a mark with a beam from the detection optical system such that an image of the mark is projected through the projection optical system.