Atom Probe Tomography

Atom probe tomography is a high-resolution technique that allows for atomic-level characterization of a sample’s structure and elemental composition. This method works by ejecting individual atoms from the sample surface as ions, which are then identified using a mass spectrometer. To facilitate this process, the sample needs to be prepared in the form of a sharp tip, allowing the ions to be accurately emitted for analysis.

Focused ion beam (FIB) milling is particularly effective for preparing samples of this type, as it enables the removal of extremely precise quantities of material. When integrated with a scanning electron microscope (SEM) in a DualBeam (FIB-SEM) system, the milling process can be visually monitored in real-time, ensuring precision and control throughout the preparation process.

APT Semiconductor Analysis

Atom Probe Tomography (APT) enables ultra-high resolution characterization of modern semiconductor devices, detecting and visualizing their complex structures and elemental compositions, even at very low concentrations. As semiconductor architectures continue to shrink, APT is increasingly relied upon for advanced analysis due to its ability to provide atomic-scale insights.

However, the effectiveness of APT analysis hinges on the preparation of high-quality, site-specific atom probe tips. Achieving this is challenging due to the stringent requirements: the needle-shaped specimen must have a tip radius smaller than 50 nm, a uniform circular cross-section to generate a symmetric electric field, a precise taper angle to facilitate evaporation events, and minimal damage during preparation.

Thermo Fisher Scientific addresses these challenges with the Thermo Scientific Atom Probe LX Software and Thermo Scientific Helios 5 FX DualBeam. This integrated solution automates the FIB-based atom probe tip milling process, providing highly accurate, repeatable, and reliable tip preparation.

With these capabilities, you can detect key phenomena such as etch-related impurities (e.g., fluorides and chlorides) at interfaces, hydrogen distribution within features, heavy metal diffusion into gate oxides, and lateral diffusion of dopants in epi-layers. Learn more about the Helios 5 FX DualBeam on the product page for further details.