US Patent 8243255 Lithographic apparatus and in-line cleaning apparatus

An immersion type lithographic apparatus includes an immersion system configured to at least partially fill an immersion space with an immersion liquid. The apparatus also includes an indicator configured to indicate whether a part of the immersion system should be cleaned and a cleaning liquid supply system configured to supply a cleaner to the part of the lithographic apparatus. The cleaner is at least one of a plurality of different cleaners. Each cleaner or combination of cleaners is configured to clean a different type and/or level of contamination in the part of the lithographic apparatus. The apparatus also includes a controller configured to control which of the plurality of cleaners is provided to the part of the lithographic apparatus, based on an indication received from the indicator.