Patent ID: 8045134
Filing Date: 2011-10-25
Classification: G03F

Abstract:
1. A lithographic apparatus, comprising: a substrate table constructed to hold a substrate; a projection system configured to project a patterned radiation beam onto a target portion of the substrate; a liquid supply system configured to fill a space between the projection system and the substrate with a liquid; a measurement system configured to measure an effect associated with a temperature fluctuation of the liquid, the measurement system comprising an optical sensor configured to sense a radiation beam passing through liquid in the space at the same time that the patterned radiation beam is projected onto the substrate held on the substrate table, the sensor arranged so as to receive the radiation beam without the radiation beam having passed through the projection system or to receive the radiation beam from the projection system before or without the radiation beam re-entering the projection system; and a control system configured to determine, from the sensed beam, an effect associated with a temperature fluctuation of the liquid and to adjust the temperature of the liquid, the effect associated with the temperature fluctuation, or both.