Electron Bessel Beam Diffraction For Precise And Accurate Nanoscale Strain Mapping

Strain has a strong effect on the properties of materials and the performance of electronic devices. Their ever shrinking size translates into a constant demand for accurate and precise measurement methods with a very high spatial resolution. In this regard, transmission electron microscopes are key instruments thanks to their ability to map strain with a subnanometer resolution. Here, we present a method to measure strain at the nanometer scale based on the diffraction of electron Bessel beams. We demonstrate that our method offers a strain sensitivity better than 2.5 x 10(-4) and an accuracy of 1.5 x 10(-3), competing with, or outperforming, the best existing methods with a simple and easy to use experimental setup.