The present invention provides an exposure apparatus which exposes a substrate, comprising a measurement unit configured to measure a height of the substrate at each of a plurality of measurement points, and a control unit configured to control the height of the substrate based on measurement results obtained by the measurement unit, and control an operation to arrange a shot region of the substrate in a first position and expose the shot region, wherein the shot region includes a plurality of partial regions, and the control unit causes the measurement unit to measure the height of the substrate by arranging the shot region in a second position different from the first position so that the number of measurement points arranged in the plurality of partial regions is larger than that when arranging the shot region in the first position.

The present invention provides an exposure apparatus which exposes a substrate, comprising a measurement unit configured to measure a height of the substrate at each of a plurality of measurement points, and a control unit configured to control the height of the substrate based on measurement results obtained by the measurement unit, and control an operation to arrange a shot region of the substrate in a first position and expose the shot region, wherein the shot region includes a plurality of partial regions, and the control unit causes the measurement unit to measure the height of the substrate by arranging the shot region in a second position different from the first position so that the number of measurement points arranged in the plurality of partial regions is larger than that when arranging the shot region in the first position.

An apparatus for securing a wafer includes a chuck, at least one O-ring disposed on the chuck, a vacuum system connected to the chuck, such that the vacuum system comprises a plurality of vacuum holes through the chuck connected to one or more vacuum pumps, and a controller configured to control the height of the at least one O-ring relative to the top surface of the chuck. The controller is connected to pressure sensors capable of detecting a vacuum. The at least one O-ring may include a plurality of O-rings.