Characterization of the Surface Contamination of Deep X-Ray Lithography Mirrors
What is it about?
Wet chemical development of exposed resist, and beam calorimetry, are applied to determine the surface condition of grazing incidence mirrors exposed to synchrotron radiation. Using this technique, the mirror reflectivity can be assessed without directly probing the surface and without the need for spectral analysis.
Why is it important?
We have developed and demonstrated a technique to determine the surface condition of grazing incidence mirrors exposed to synchrotron radiation. Using this technique, the mirror reflectivity can be assessed without directly probing the surface and without the need for spectral analysis. The developed analysis technique allows an indirect way to qualify a mirror surface. It can be applied at synchrotron beamlines that do not have the space for diffractive analysis or that have too high a flux for energy-dispersive detectors, and that do not have capabilities to probe the mirror surface directly. Results obtained from such analysis, in combination with the DXRL exposure parameter simulation tool developed, allow to predict the actual DXRL dose deposition for any solid material used as vacuum window, filter, or mirror surface, and for multiple mirror surface layers. It thus helps to adjust DXRL process conditions to X-ray optical elements in non-ideal conditions or with novel materials, potentially improving the structure quality of fabricated microstructures.