A unique approach to accurately measure thickness in thick multilayers

Area of Science:

• Materials Science
• Optics
• Nanotechnology

Background:

• Multilayer Laue lenses (MLLs) are advanced X-ray optics for high-resolution focusing.
• Fabricating MLLs involves depositing thousands of precisely controlled thin layers.
• Current methods struggle with accurate thickness measurement of these numerous layers, impacting MLL performance.

Purpose of the Study:

• To develop and validate a novel metrology approach for accurate thickness measurement of MLL layers.
• To address the challenge of layer thickness errors in MLL fabrication.
• To improve the precision and reliability of MLL structures.

Main Methods:

• A new metrology technique using a focused ion beam (FIB) to introduce regular marks on the cross-section of MLLs.
• Comparison of the new FIB-based measurement method with a previous measurement technique.
• Characterization of magnetron sputter-deposited WSi(2)/Si MLLs at a synchrotron X-ray nanoprobe beamline.

Main Results:

• The new FIB metrology approach enables accurate measurement of the thickness of thousands of individual layers in MLLs.
• The new method provides more accurate thickness results compared to previous techniques.
• Demonstrated feasibility of precise layer thickness control for improved MLL fabrication.

Conclusions:

• The developed FIB metrology is a significant advancement for the accurate fabrication of multilayer Laue lenses.
• This improved metrology will lead to higher quality X-ray optics with enhanced focusing efficiency and resolution.
• The findings pave the way for more reliable and precise nanostructure fabrication in X-ray optics.