Patent ID: 9477155
Filing Date: 2016-10-25
CPC Classification: G01B,G03F,H01L,Y10T

Claim Text:
1. An exposure apparatus which exposes an object with an illumination light via a projection optical system, the apparatus comprising: a stage having a holder configured to hold the object; a driving system having an electromagnetic motor, which drives the stage by the electromagnetic motor, a part of the electromagnetic motor being provided at the stage; an encoder system having a plurality of heads provided at the stage, which measures positional information of the stage by irradiating a measurement beam from below via each of the plurality of heads onto a measurement plane arranged substantially parallel to a predetermined plane perpendicular to an optical axis of the projection optical system; and a controller coupled with the driving system and the encoder system, which controls a drive of the stage based on the measured positional information, wherein the measurement plane is defined by a plurality of scale plates which are arranged around an exposure position where exposure of the object is performed via the projection optical system and on each of which a reflective grating is formed, in a part including the exposure position, of a first movement area where the stage is moved in an exposure operation of the object, the encoder system is capable of measuring the positional information of the stage by the plurality of heads that respectively face the plurality of scale plates, and in another part of the first movement area, the encoder system is capable of measuring the positional information of the stage by remaining heads after excluding one head of the plurality of heads, and the controller decides calibration information of the encoder system based on the positional information of the stage measured by the encoder system in the part including the exposure position of the first movement area.