©Laser-absorption Oxygen Monitor for Beam-Sealed ArF Laser System
Publication Date: 2003-Sep-18
The IP.com Prior Art Database
©Purpose and advantage of invention: To periodically check purge integrity of a beam-sealed laser system and optics modules without the need for an expensive oxygen monitor. Short description of invention (Include or attach appropriate sketches, and point out novel features): Laser software would incorporate an automated wavelength scan option (like that used in AWR). The power at the autoshutter would be recorded as a function of wavelength. Software would look for an absorption dip at the wavelengths corresponding to oxygen lines, and use the size of the dip to estimate the oxygen concentration in the beam-sealed volume and modules. If this number is out-of-spec, the laser would shut down and alert the operator to a condition which could damage the optics. Such a procedure could be performed concurrently with the AWR and auto power calibration on the XL series product.