The quantum efficiency of pn-detectors from the near infrared to the soft X-ray region

The quantum efficiency of back-illuminated silicon pn-junction detectors is evaluated in the spectral range from 1.2 to 1400 eV, comprising the near infrared, visible, ultraviolet and soft X-ray regions. The calibrations are performed with the same device over the entire measured range, thus eliminating technological variations of the entrance window. Recent technological developments have yielded detectors with near-theoretical quantum efficiencies.