Exposure method, exposure apparatus, and device manufacturing method

摘要

Within area where of four heads installed on a wafer stage, heads included in the first head group and the second head group to which three heads each belong that include one head different from each other face the corresponding areas on a scale plate, the wafer stage is driven based on positional information which is obtained using the first head group, as well as obtain the displacement (displacement of position, rotation, and scaling) between the first and second reference coordinate systems corresponding to the first and second head groups using the positional information obtained using the first and second head groups. By using the results and correcting measurement results obtained using the second head group, the displacement between the first and second reference coordinate systems is calibrated, which allows the measurement errors that come with the displacement between areas on scale plates where each of the four heads face.

主权项

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.