3-Dimensional Lineshape Metrology Using Small Angle X-ray Scattering

The need for sub‐nanometer precision metrology of dense patterns for future technology nodes challenges current methods based on light scatterometry, scanning electron microscopy (SEM), and atomic force microscopy (AFM). We provide results of initial tests of a measurement technique based on small angle x‐ray scattering (SAXS) capable of rapid measurements of test samples produced using conventional test masks without significant sample preparation. The sub‐Angstrom wavelength provides nanometer level resolution, with the possibility of increased precision after further refinement of the technique. SAXS results are shown for a test photoresist grating at a variety of angles, demonstrating an ability to extract information on 3‐dimensional pattern shape.