| 摘要 |
PROBLEM TO BE SOLVED: To prolong the service lives of a lens material and its surface by constituting the internal surface of a laser chamber, so that the internal surface cannot reflect light having specific wavelengths and the outermost surface of the internal surface of a fluoride and providing a microwave introducing means, and then, specifying the reflectivity of an output-side reflecting mirror. SOLUTION: A cylindrical optical resonator is used, and the internal surface of the resonator is constituted so that the internal surface cannot reflect light having desired wavelengths of 248nm, 193nm, 157nm, etc. In addition, the outermost surface of the internal surface is constituted of a fluoride. The inside of a waveguide 42 is evacuated to a vacuum, and a non-reflective film having a fluoride outermost surface is formed on an insulating plate 44. The supply frequency of microwaves is set at 35GHz, and the laser gas is prepared by mixing Kr, Ne, and gases at a mixing ratio of 3%:92%:5%. When a chemically amplified resist is formed by using a continuous light-emitting excimer laser oscillator using a light-reflecting plate 6 having reflectivity of >=90%, the service lives of the resist and its surface can be prolonged, because the resist can be formed with an optical output of about 10W, even when the loss of the optical system is taken into consideration when the resist is exposed for 0.2sec to a light of 0.1W/cm at sensitivity of about 20mj/cm. |
