Measurement apparatus, lithography apparatus, and method of manufacturing article

A lithography apparatus for forming a pattern on a substrate, comprising:

• a stage configured to be movable while holding the substrate;
• and
• a measurement apparatus configured to measure a position of the stage as an object,
• wherein the measurement apparatus includes:
• a reflecting portion provided on the object and having a reflecting surface on which a plurality of reflectors configured to respectively retroreflect light are arrayed;
• an optical system configured to cause first light to be incident on the reflecting surface, receive second light as reflected light of the first light from the reflecting surface, cause third light generated by reflecting the second light by a mirror member to be incident on the reflecting surface, and receive fourth light as reflected light of the third light from the reflecting surface;
• and
• a processor configured to determine the position of the object based on a result of detecting the fourth light and a reference light,
• wherein the plurality of reflectors are arrayed on the reflecting surface such that a displacement between optical paths of the first light and the second light is corrected by a displacement between optical paths of the third light and the fourth light.

A method of manufacturing an article, the method comprising:

• forming a pattern on a substrate using a lithography apparatus;
• and
• processing the substrate, on which the pattern has been formed, to manufacture the article,
• wherein the lithography apparatus includes a stage configured to be movable while holding the substrate, and a measurement apparatus configured to measure a position of the stage as an object, and
• wherein the measurement apparatus includes:
• a reflecting portion provided on the object and having a reflecting surface on which a plurality of reflectors configured to respectively retroreflect light are arrayed;
• an optical system configured to cause first light to be incident on the reflecting surface, receive second light as reflected light of the first light from the reflecting surface, cause third light generated by reflecting the second light by a mirror member to be incident on the reflecting surface, and receive fourth light as reflected light of the third light from the reflecting surface;
• and
• a processor configured to determine the position of the object based on a result of detecting the fourth light and a reference light,
• wherein the plurality of reflectors are arrayed on the reflecting surface such that a displacement between optical paths of the first light and the second light is corrected by a displacement between optical paths of the third light and the fourth light.