Lithographic flare measurements of Intel’s microexposure tool optics Available to Purchase

Measurements of flare as a function of feature size, pitch, and orientation have been made on Intel’s extreme ultraviolet microexposure tool (MET) using a high sensitivity photoresist. The high sensitivity photoresist does not cross-link at the high doses required to measure flare. The predicted value for intrinsic flare for the MET from mid-spatial frequency roughness (MSFR) of mirror surfaces is 3.5%. After addition of the contribution to flare from high order aberrations to that from MSFR, the modeled value is in excellent agreement with the measured flare for the $1μm$ line of 4%. The measured flare in the horizontal direction is 5% and is higher than the flare in the vertical direction. The point spread function due to scatter has been computed and the modulation transfer function of the system as a function of pitch has also been measured.