A photolithographic apparatus in which a light source exposes a substrate for patterning includes an enclosure having a controllable internal ambient for transferring the substrate in and out of the apparatus, a gate valve through which the substrate is transferred into or out of the enclosure, and a...http://www.google.com/patents/US6638672?utm_source=gb-gplus-sharePatent US6638672 - Exposure apparatus, coating/developing apparatus, method of transferring a substrate, method of producing a device, semiconductor production factory, and method of maintaining an exposure apparatus
