A method to monitor the state of polarization incident on a photomask in projection printing is presented. The method includes a series of phase-shifting mask patterns that take advantage of high NA effects to create a signal dependent on only one incident polarization component. The patterns include in two embodiments a Radial Phase Grating (RPG) and Proximity Effect Polarization Analyzers (PEPA). A test reticle design includes multiple polarimeters with an array of pinholes on the backside of the photomask. This technique is able to monitor any arbitrary illumination scheme for a particular tool.

 
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> Mapping-measurement apparatus

~ 00350