ALIGNER, DEVICE MANUFACTURING METHOD, MAINTENANCE METHOD AND ALIGNING METHOD

摘要

An aligner which eliminates a problem of supplying a liquid having deteriorated cleanliness and a problem of forming a water mark. The aligner (EX) projects exposure light (EL) on a substrate (P) through a projection optical system (PL) and a liquid (LQ) and exposes the substrate (P). The aligner is provided with a liquid supplying mechanism (10) for supplying the liquid (LQ) and measuring equipment (60) for measuring a time when the liquid supply from the liquid supplying mechanism (10) is stopped.