February 2023

Symbolic picture for the article. The link opens the image in a large view.

This image reminds us on confetti, which fits to the carnival season!
Every color represents a specific in-plane orientation of the nano-crystallites. This orientation mapping of AlN crystallites was acquired with 4D-STEM, an advanced technique collecting the electron diffraction patterns at each probed position using a fast camera that can record ~100.000 diffraction patterns per second. These 4-dimensional datasets allow the analysis of the crystal structure and orientation at each point by matching a library of simulated patterns. Due to a specific growth process, the AlN film grows into columns with [0001] fiber texture and the plan-view (in-plane) geometry can be seen in the image.