Patent ID: 9551944
Date: 2017-01-24
CPC Classifications: B08B,B23P,G03F,Y10T

Claim:
1. A method, comprising: providing an objective having an objective interior and objective parts provided therein, an objective part of the objective parts being replaceably accommodated in the objective interior, wherein the objective interior is sealed off from an ambient atmosphere by a closure, providing a cleaning room that is unattached to the objective; and further comprising the following operations performed in sequence as herein below recited: discharging the impurities from the cleaning room into the ambient atmosphere, after the cleaning and the discharging, and while the cleaning room is attached to the objective, opening the closure and installing the replacement objective part without the impurities in the objective interior while the cleaning room and the objective interior are sealed off from the ambient atmosphere, sealing the objective interior, including the replacement objective part installed therein, from the ambient atmosphere and the cleaning room; detaching the cleaning room from the objective; and operating the objective by irradiating the replacement objective part with objective light, wherein the objective part comprises at least one of an optical element imaging the objective light reflected and/or refracted from a reticle and an optical element of an illumination projection system imaging the objective light onto a reticle.