PATTERN DETECTOR AND ITS USING METHOD, MEASURING METHOD AND APPARATUS, POSITION MEASURING METHOD, EXPOSING METHOD AND DEVICE, AND METHOD FOR FABRICATING DEVICE

摘要

Under a first state where the positional relation between a wafer W and an alignment sensor (14) is in a specified state, a main controller (20) irradiates an area in the vicinity of an alignment mark on the wafer W with a first imaging light flux, and detects the XY positional information of the mark after adjusting the Z position of the wafer based on the imaging light flux reflected off the wafer surface. Subsequently, that area is irradiated with a second imaging light flux under a second state where the wafer is turned by 180 from the first state, and the XY positional information of the mark is detected after adjusting the Z position of the wafer based on the imaging light flux reflected off the wafer surface. Since the same area is irradiated with each of imaging light fluxes, focus state before turning the wafer can be reproduced accurately after turning the wafer. A detection lag caused by the detection system and a detection lag caused by the formational state of the mark can be calculated accurately using the positional information thus obtained.