The large 100 mm2 and 170 mm2 SDD sensors of Ultim Max allows up to 17x more data to be collected in the same time with no loss of accuracy. Whether you want to map larger areas, have better statistics in each data point, collect data much faster, or investigate the smallest nano-structures, Ultim Max is the ultimate solution for X-ray analysis in the SEM.

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The X-MaxN range of Silicon Drift Detector exploits a new sensor chips, new electronics, and innovative packaging to deliver a truly ‘next generation’ SDD X-MaxN is a range of advanced Silicon Drift Detectorsperformance.

The X-MaxN Silicon Drift Detector comes in a range of detector sizes, from 20 mm2 for microanalysis up to an astounding 150 mm2 for advanced nanoanalysis.


  • A range of silicon drift detector sizes, from 150 mm2 to 20 mm2
  • X-MaxN provides a superb resolution that is independent of sensor size - specifications guaranteed to ISO15632:2012
  • The same mechanical geometry inside the microscope means that the count rate simply increases in proportion to sensor size
  • Excellent low energy analysis, including Be detection guaranteed on all sensor sizes
  • Fits to SEMs and FIBs using the same interface as the previous generation X-Max
  • Up to four X-MaxN can run in parallel on one microscope to create a system with a total active area of 600 mm2

See X-Max Extreme for the ultimate EDS spatial performance in FEG-SEM


AZtecLive & Ultim Max Brochure

AZtecLive takes the EDS technique from the static to the dynamic with real-time chemical imaging. AZtecLive is powered by Ultim Max, the next generation SDD detectors combining the largest sensor sizes (170 mm2 and 100 mm2) with Extreme electronics to deliver unparalleled speed and sensitivity.

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AZtecEnergy EDS Microanalysis software characterises material composition of samples inside a SEM or FIB. This 20 page brochure shows why AZtecEnergy is the world's leading EDS solution.

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From 20mm2 to a combined working area of 600mm2, the X-MaxN range of Silicon Drift Detectors provides a powerful solution for EDS analysis in the SEM. This 12 page brochure shows why.

X-Max Extreme

The X-Max Extreme is a windowless 100mm2 version of X-Max designed to maximise sensitivity and spatial resolution. It uses a radical geometry to optimise both imaging and EDS performance in ultra-high resolution FEG-SEMs. The 4 page brochure shows some of the applications.

PDF 6.05MB

SDD Tutorial

SDD Explained

EDS (Energy Dispersive Spectroscopy) is an established technique used to characterise the elemental composition of a sample under the beam of an electron microscope.

This 20+ page brochure will explain more.

PDF 1.91MB

X-MaxN Features

Performance independent of size

X-MaxN comes in a range of detector sizes, 20mm2, 50mm2, 80mm2 and 150mm2.

  • X-MaxN resolution and low energy detectability is independent of sensor size because of its external FET design.
  • The same sensor position means that the count rate simply increases in proportion to sensor size
  • The same outstanding resolution performance is guaranteed on all sensor sizes
  • Excellent low energy analysis, including Be detection on all sensor sizes
  • LN2 not required. X-MaxN is ready to start working in minutes and has full overheat protection.

X-MaxN resolution does not vary with detector size

With AZtecEnergy and X-MaxN, data from multiple detectors can be seamlessly combined for even greater sensitivity.

  • Increase count rate, with no loss in spatial or spectrum resolution
  • Up to four detectors on one microscope
  • Up to 600 mm2 real active area!


  • Collect X-ray maps using only a few pA on the most unstable samples
  • Maximise information from the smallest nano-particles and features
  • Quantitative analysis with pulse pile-up correction at many 100s of thousand counts per second
  • Detect low concentrations of minor elements faster

Multiple detectors - example

X-MaxN Benefits

Using a large sensor means:

  • Productive count rates at low beam currents
  • Maximising imaging performance and accuracy
  • No need to change imaging conditions for X-ray analysis
  • Significantly higher count rates at the same beam current
  • Shorter acquisition times
  • Better statistical confidence
  • Practical analysis with small beam diameters
  • Maximising spatial resolution
  • Getting the best out of your high resolution SEM


Size matters, sensitivity counts

Under the same operating conditions, bigger detectors:

  • Will do in seconds what used to take minutes – mapping can be an everyday tool
  • Will dramatically improve precision for the same acquisition time

Large Area detectors – high-speed microanalysis is routine for all.


Low energy spectra easily identifiedLow energy matters, sensitivity counts

X-MaxN is optimised for low energy performance – no compromise on size. Nothing else comes close.

  • Be detection guaranteed on all detectors, Si Ll can be mapped

Very Large Area detectors – low energy analysis is practical for all.

Size matters, spatial resolution counts

High spatial resolution conditions give low X-ray yield.

  • Large area detectors collect high quality low energy spectra in practical time scales
  • Nanoscale features can be better characterised

Very Large Area detectors – advanced nanoanalysis is possible for all.

Why size matters

What does a 150 mm2 detector do better than a smaller detector?

Take an example. At 20 kV a 150 mm2 detector requires less than 2 nA to generate 200,000 counts per second. In contrast, a 10 mm2 detector requires nearly 20 nA

The graph below shows typical count rate at different beam currents, when analysing Pure-Mn at 20 kV using a detector with 30° take off angle and 45 mm sample to crystal distance. Using a larger sensor, count rates are increased without increasing beam current. This means productive count rates are achieved under conditions where spatial resolution is maximised and beam damage minimised. The images to the left show the potential effects of increasing beam current on image quality.


Click the images to expand.













The effect of beam current on nanoscale analytical capability

When using smaller detectors, the high beam current required to achieve usable count rate leads to poor spatial resolution. The X-MaxN 150 Very Large Area detector acquires high count rates at excellent spatial resolution, for successful analysis of the smallest nanostructures.





Right: X-ray mapping of fragile nanostructures at 5 kV. For the same count rate, a 150 mm2 detector requires much lower beam current, meaning that the spatial resolution is good enough to clearly show nanoscale variations and minimise specimen damage. In contrast, higher beam current required for 10 mm2 results in loss of nanoscale resolution and significant damage during the map collection.










Why size matters (3)




Right: X-ray maps collected at 0.2 nA, 3 kV using 150 mm2 X-MaxN detector to investigate nanostructures in a memory alloy. Variations in Fe La, Ni La and Cu La clearly demonstrate chemical differences on a scale down to at least 20 nm.








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