Movable body drive method and movable body drive system, pattern formation method and apparatus, exposure method and apparatus, and device manufacturing method

An exposure method of exposing a substrate with an illumination light via a projection optical system, the method comprising:

• holding a mask with a first stage disposed above the projection optical system;
• holding the substrate with a second stage disposed below the projection optical system;
• measuring positional information of the first stage and positional information of the second stage with a first encoder system and a second encoder system, respectively, wherein
• at least in an exposure operation of a plurality of areas to be exposed on the substrate, in the second encoder system in which one of a grating section that has four scale members and a plurality of heads that each irradiate the grating section with a beam is provided at the second stage, the positional information of the second stage is measured with at least three heads, of the plurality of heads, the at least three heads always facing at least three of the four scale members, respectively, and
• each of the four scale members has a reflective grating that is periodic in a direction parallel to a predetermined plane orthogonal to an optical axis of the projection optical system;
• moving the first and the second stages based on measurement information of the first and the second encoder systems so that scanning exposure is performed with a first direction within the predetermined plane serving as a scanning direction in the exposure operation, in the scanning exposure the mask and the substrate being each moved relative to the illumination light;
• switching one head of the three heads that face three of the four scale members, respectively, to another head, as the second stage is moved in a direction parallel to the predetermined plane, the another head being different from the three heads used before the switching, of the plurality of heads;
• and
• acquiring correction information of the positional information measured with the another head, based on the positional information measured with the three heads used before the switching, wherein
• after the switching, the positional information of the second stage is measured with three heads including two heads and the another head, the two heads excluding the one head of the three heads used before the switching.

A method of making an exposure apparatus that exposes a substrate with an illumination light via a projection optical system, the method comprising:

• providing a first stage system having a first stage and a first drive system, the first stage being disposed above the projection optical system and holding a mask illuminated with the illumination light, and the first drive system including a first motor coupled to the first stage;
• providing a second stage system having a second stage and a second drive system, the second stage being disposed below the projection optical system and holding the substrate, and the second drive system including a second motor coupled to the second stage;
• providing a measurement system having a first encoder system and a second encoder system, wherein
• the first encoder system measures positional information of the first stage,
• in the second encoder system, one of a grating section that has four scale members and a plurality of heads that each irradiate the grating section with a beam is provided at the second stage,
• at least in an exposure operation of a plurality of areas to be exposed on the substrate, the second encoder system measures positional information of the second stage with at least three heads, of the plurality of heads, the at least three heads always facing at least three of the four scale members, respectively, and
• each of the four scale members has a reflective grating that is periodic in a direction parallel to a predetermined plane orthogonal to an optical axis of the projection optical system;
• and
• providing a controller coupled to the first and the second stage systems and the measurement system, the controller controlling the first and the second drive systems based on measurement information of the first and the second encoder systems so that scanning exposure is performed with a first direction within the predetermined plane serving as a scanning direction in the exposure operation, in the scanning exposure the mask and the substrate being each moved relative to the illumination light, wherein
• one head of three heads that face three of the four scale members, respectively, is switched to another head, as the second stage is moved in a direction parallel to the predetermined plane, the another head being different from the three heads used before the switching, of the plurality of heads,
• the controller acquires correction information of the positional information measured with the another head, based on the positional information measured with the three heads used before the switching, and
• after the switching, the positional information of the second stage is measured with three heads including two heads and the another head, the two heads excluding the one head of the three heads used before the switching.