Scanning transmission electron microscope Spectra Ultra

for quality controlfor materials researchfor semiconductors

Scanning transmission electron microscope for imaging and spectroscopy of beam sensitive materials. Spectra Ultra Scanning Transmission Electron Microscope To truly optimize TEM and STEM imaging, EDX and EELS may require acquisition of different signals at different accelerating voltages. The rules may vary from sample to sample but, it is generally accepted that: 1) the best imaging is done at the highest possible accelerating voltage above which visible damage will occur, 2) EDX, especially when mapping, benefits from lower voltages with increased ionization cross-sections, thus yielding better signal-to-noise ratio maps for a given total dose, and 3) EELS works best at high voltages to avoid multiple scattering, which degrades the EELS signal with increasing sample thickness. Unfortunately, acquisition at different accelerating voltages on the same sample without losing the region of interest—all during a single microscopy session—is not possible. At least, until now. Imagine a Thermo Scientific Spectra 300 S/TEM: • That can truly be operated at different voltages (all the voltages between 30 and 300 kV for which alignments were purchased) in a single microscopy session • Where changing from an accelerating voltage to any other one takes about 5 minutes • That can accommodate a radically different EDX concept with a 4.45 srad solid angle (4.04 srad solid angle with an analytical double tilt holder) With the new Spectra Ultra S/TEM, the accelerating voltage becomes an adjustable parameter, just like probe current, and the massive Ultra-X EDX system enables chemical characterization of materials too beam-sensitive for conventional EDX analysis.