Photolithographic position measuring laser interferometer with relitively moving measuring intereometer

A position measuring apparatus for measuring, with a light from a light source, the position of a moving object in a first direction orthogonal to a second direction when the object moves in the second direction, the position measuring apparatus comprising:

• a separating optical system for separating the light from the light source into a measurement beam and a reference beam;
• a moving mirror which is attached to the moving object and reflects the measurement beam;
• a fixed mirror which is provided independently from the moving object and defines part of an optical path for the measurement beam between the moving mirror and the fixed mirror;
• a moving device for moving the separating optical system in the second direction at a speed different from the speed of the moving object;
• and
• a detecting system for detecting the measurement beam and reference beam and determining the position of the moving object in the first direction on the basis of interference effect of the beams.

An exposure apparatus for transferring a pattern formed on a mask onto a substrate, the exposure apparatus comprising:

• a mask stage for holding the mask thereon and moving the mask in a second direction;
• a substrate stage for holding the substrate thereon and moving the substrate in the second direction;
• and
• a laser interferometer for measuring with a laser beam the position of at least one of the stages in a first direction orthogonal to the second direction;
• the laser interferometer including:
• a separating optical system for separating the laser beam into a measurement beam and a reference beam;
• a moving mirror which is attached to at least one of the stages and reflects the measurement beam;
• a reference mirror which is provided independently from at least one of the stages and reflects the reference beam;
• a moving device for moving the separating optical system in the second direction at a speed different from the speed of the at least one of the stages;
• and
• a detector for detecting the measurement beam reflected from the moving mirror and the reference beam reflected from the reference mirror, and determining the position of the at least one of the stages in the first direction on the basis of interference effect of the beams.

An exposure apparatus for transferring a pattern formed on a mask onto a substrate, the exposure apparatus comprising:

• a mask stage for holding the mask and moving the mask in a second direction;
• a substrate stage for holding the substrate and moving the substrate in the second direction;
• and
• a position measuring apparatus for measuring with a light beam the position of at least one of the stages in a first direction orthogonal to the second direction;
• the position measuring apparatus including:
• a separating optical system for separating the light beam into a measurement beam and a reference beam;
• a moving mirror which is attached to the at least one of the stages and reflects the measurement beam;
• a fixed mirror which is provided independently from the at least one of the stages and defines part of an optical path for the measurement beam between the moving mirror and the fixed mirror;
• a moving device for moving the separating optical system in the second direction at a speed different from the speed of the at least one of the stages;
• and
• a detecting system for detecting the measurement beam and reference beam and determining the position of the at least one of the stages in the first direction on the basis of interference effect of the beams.

A position measuring method for measuring a position of a moving object in a first direction orthogonal to a second direction based on interference effect by directing a laser beam toward a fixed mirror and a moving mirror attached to the moving object which travels in the second direction, the method comprising the steps of:

• separating the laser beam into a measurement beam and a reference beam;
• directing the measurement beam toward the moving mirror while moving the measurement beam in the second direction at a speed different from that of the moving object being moved, and passing the light reflected from the moving mirror between the moving mirror and the fixed mirror;
• and
• determining the position of the moving object in the first direction by comparing the phase of the reference beam and the phase of the measurement beam passed between the moving mirror and the fixed mirror.

A method for manufacturing a laser interferometer for measuring, with a laser beam, the position of a moving object in a first direction orthogonal to a second direction when the object moves in the second direction, comprising:

• providing a separating optical system for separating the laser beam into a measurement beam and a reference beam;
• providing, on the moving object, a moving mirror for reflecting the measurement beam;
• providing a reference mirror which is provided independently from the moving object and reflects the reference beam;
• providing a moving device for moving the separating optical system in the second direction at a speed different from the speed of the moving object;
• and
• providing a detector for detecting the measurement beam reflected from the moving mirror and the reference beam reflected from the reference mirror, and determining the position of the moving object in the first direction on the basis of interference effect of the beams.

A method for manufacturing a position measuring apparatus for measuring, with a light from a light source, the position of a moving object in a first direction orthogonal to a second direction when the object moves in the second direction, comprising:

• providing a separating optical system for separating the light from the light source into a measurement beam and a reference beam;
• providing, on the moving object, a moving mirror for reflecting the measurement beam;
• providing a fixed mirror which defines part of an optical path for the measurement beam between the moving mirror and the fixed mirror;
• providing a moving device for moving the separating optical system in the second direction at a speed different from the speed of the moving object;
• and
• providing a detecting system for detecting the measurement beam and reference beam and determining the position of the moving object in the first direction on the basis of interference effect of the beams.

A method for manufacturing an exposure apparatus for transferring a pattern formed on a mask onto a substrate, comprising:

• providing a mask stage for holding the mask and moving the mask in a second direction;
• providing a substrate stage for holding the substrate and moving the substrate in the second direction;
• providing a separating optical system for separating a laser beam into a measurement beam and a reference beam;
• providing on at least one of the mask stage and the substrate stage a moving mirror for reflecting the measurement beam;
• providing a reference mirror for reflecting the reference beam;
• providing a moving device for moving the separating optical system in the second direction at a speed different from the speed of the at least one of the stages;
• and
• providing a detector for detecting the measurement beam reflected from the moving mirror and the reference beam reflected from the reference mirror, and determining the position of the at least one of the stages in the first direction on the basis of interference effect of the beams.

A method for manufacturing an exposure apparatus for transferring a pattern formed on a mask onto a substrate, the manufacturing method comprising:

• providing a mask stage for holding the mask and moving the mask in a second direction;
• providing a substrate stage for holding the substrate and moving the substrate in the second direction;
• providing a separating optical system for separating the light into a measurement beam and a reference beam;
• providing on at least one of the mask stage and the substrate stage a moving mirror for reflecting the measurement beam;
• providing a fixed mirror which defines part of an optical path for the measurement beam between the moving mirror and the fixed mirror;
• providing a moving device for moving the separating optical system in the second direction at a speed different from the speed of the at least one of the stages;
• and
• providing a detecting system for detecting the measurement beam and reference beam and determining the position of the at least one of the stages in the first direction on the basis of interference effect of the beams.

A position measuring apparatus for measuring, with a laser beam from a light source, a position of a moving object in a first direction orthogonal to a second direction when the object moves in the second direction, the position measuring apparatus comprising:

• a moving mirror attached to the moving object, and a fixed mirror provided independently from the moving object;
• an optical system for splitting the light beam from the light source and directing the split beams individually toward the moving mirror and the fixed mirror;
• a moving device for moving the optical system in the second direction at a speed different from the speed of the moving object;
• and
• a detector for detecting the light beams reflected from the moving mirror and the fixed mirror, and determining the position of the moving object in the first direction on the basis of interference effect of the beams.