Lambda for Electron Microscopy

Lambda Electron

All our detectors, in any sizes, can be used in vacuum and for electron detection. Vacuum units are always water-cooled.

Talk to us if you need a special design.

Sensor Options

Graphic

LAMBDA with High-Z sensor is well suited for energies above 20 keV

X-Spectrum has developed versions of the LAMBDA system where the silicon sensor is replaced with one of the “high-Z“ materials, Gallium Arsenide (GaAs) or Cadmium Telluride (CdTe), which provide greater detection efficiency at high X-ray energies. With these sensors, the LAMBDA system combines efficient hard X-ray detection with zero noise, high spatial resolution and high speed. In particular, the 2000 frames per second readout of a high-Z LAMBDA system is more than 1000 times faster than a typical flat-panel detector, enabling time-resolved hard X-ray experiments on millisecond timescales.

Sensor material: Gallium Arsenide or
Cadmium Telluride

As shown to the right, Cadmium Telluride has higher quantum efficiency than Gallium Arsenide at higher X-ray energies, so it is the natural choice for experiments at 60 keV and above. However, CdTe also strongly re-emits fluorescence photons around 25-30 keV when illuminated with higher-energy photons, which can reduce the detected signal and slightly blur the image.

So, GaAs is beneficial in the 25 – 50 keV range. After flat-field correction, GaAs sensors also deliver better image uniformity.

If you consider using high-Z material, contact our sales department beforehand. Together, we’ll find the best solution for your experiment.

Depending on the sensor material the following specifications are valid:

Si GaAs CdTe
Energy range: 6 – 25 keV 8 – 75 keV 8 – 150 keV
Adjustable threshold range: 4 – 40 keV 5 – 50 keV 5 – 75 keV