Spectra Ultra S/TEM

Ideal optimization of S/TEM imaging requires EDX and EELS to acquire different signals at different acceleration voltages. The conditions may differ from one sample to another. However, it is widely accepted that:

The best imaging is executed at the highest possible accelerating voltage, and crossing it leads to visible damage.

EDX, particularly when mapping, benefits from lower voltages with elevated ionization cross-sections, which results in better signal-to-noise ratio maps for a specified total dose.

EELS performs better at high voltages to inhibit multiple scattering, which affects the EELS signal with an increase in sample thickness.

However, so far, it has not been possible to acquire different accelerating voltages on the same sample without the loss of the region of interest — all in a single microscopy session.

Visualize a Thermo Scientific Spectra 300 S/TEM:

That can really work at different voltages (between 30 and 300 kV, for which alignments were bought) in a single microscopy session

Where a change from one accelerating voltage to another requires about 5 minutes

That can house a radically different EDX concept with a 4.45 srad solid angle (4.04 srad solid angle with an analytical double tilt holder)

The new Spectra Ultra S/TEM offers adjustable accelerating voltage, quite similar to how the probe current is adjustable, and the massive Ultra-X EDX system allows chemical characterization of materials that are highly beam-sensitive for traditional EDX analysis.

The Spectra Ultra aberration-corrected S/TEM provides best-in-class characterization capabilities for semiconductor and materials science applications at the highest resolution on an extensive range of samples.

Built on an Ultra-Stable Foundation

The Spectra Ultra S/TEM comes on a platform created to deliver an unmatched level of mechanical stability and quality through (optional) active and passive vibration isolation.

Similar to the Thermo Scientific Spectra 200 S/TEM and Spectra 300 S/TEM, the Spectra Ultra S/TEM system is accommodated in a completely redesigned enclosure with an integrated on-screen display for convenient loading and removal specimen.

Complete modularity and upgradeability can be offered, for the first time, between single-corrected and uncorrected configurations with variable heights. This ensures maximum flexibility for various room configurations.

Key Features

In situ capabilities of the Spectra Ultra S/TEM

Unprecedented sensitivity with the Panther STEM detection system

Delivers advanced STEM imaging capabilities

Lowest dose of STEM/EDX to characterize more materials

Quickest time to acquire optimized results from more materials

High-energy resolution and high brightness sources

Delivers STEM imaging performance of highest resolution

Specifications

Source: Thermo Fisher Scientific – Electron Microscopy Solutions