Patent ID: 7382435

Claim:
An exposure apparatus which irradiates, with an exposure beam through a projection optical system, a photosensitive agent applied to a substrate to form a latent image pattern on the photosensitive agent, said apparatus comprising: a substrate stage which drives the substrate; a focus measurement unit which obliquely irradiates the substrate with measurement light to measure a position of the substrate in a direction of an axis of the exposure beam based on the light reflected by the substrate; and a controller which executes calibration for correcting, based on a measurement result obtained by said focus measurement unit, a track plane of said substrate stage with reference to a reference plane of said focus measurement unit so as to set the track plane parallel to the reference plane, wherein said substrate stage includes a reference plate and said controller controls, when measurement for correcting the track plane of said substrate stage is to be executed by said focus measurement unit, a position of said substrate stage so as to irradiate said reference plate with the measurement light.