Advanced Detectors, Systems, & Nanoscience
World Record Sensitivity with Solid-State Photon-Counting Arrays in Far Ultraviolet
MDL researchers have demonstrated imaging arrays with >50% external QE in the FUV using MBE for delta doping and ALD for advanced antireflection coatings. This QE is about an order of magnitude higher than the GALEX detector and sets an unprecedented high sensitivity in this very challenging part of the spectrum. Another significant accomplishment has been the demonstration of delta-doped electron-multiplied CCDs (EMCCDs) by performing end to end post-fabrication back-illumination processing including thinning, delta doping, antireflection coatings, packaging, and characterizing fully fabricated e2v’s low light level CCDs (L3CCDs). The delta-doped L3CCDs exhibited near 100% internal QE, indicating that the only loss of photons is due to the reflection from the back surface of the device. Adding the antireflection coatings to this device, MDL has demonstrated >50% QE using advanced AR-coating for the 100–300 nm spectral range. The combination of high QE and photon counting makes it possible to replace microchannel plate-based detectors that were used in GALEX and enable imaging and spectroscopy for exciting new missions.