XTEM

XTEM, which stands for Cross-sectional Transmission Electron Microscopy, is a powerful imaging technique used to visualize the internal structure of materials at the nanoscale. Unlike conventional Transmission Electron Microscopy (TEM) which typically examines thin samples from above, XTEM allows for the examination of the material's cross-section, revealing information about interfaces, layers, and defects in three dimensions.

The process of preparing a sample for XTEM involves several critical steps. First, the material of interest is carefully sectioned. This is often followed by embedding the sample in a resin to provide structural support. The crucial step is then creating an ultra-thin cross-section, typically on the order of tens to hundreds of nanometers. This is achieved through specialized techniques such as focused ion beam (FIB) milling or mechanical polishing. Once the cross-section is prepared, it is placed on a TEM grid.

In the TEM instrument, an electron beam is transmitted through the ultra-thin cross-section. Different parts of the sample interact with the electron beam differently, scattering electrons to varying degrees based on their atomic number and density. These transmitted electrons are then captured by a detector, forming an image that represents the internal structure of the cross-section. XTEM is particularly valuable in fields such as semiconductor manufacturing, where it is used to inspect the intricate layers and structures of integrated circuits, and in materials science for analyzing the microstructure of composites, coatings, and nanoparticles. The detailed insights provided by XTEM are essential for understanding material properties, diagnosing failures, and guiding the development of new advanced materials.