Al0.2Ga0.8As 2 x 2 square pixel X-ray photodiode array

作者：Whitaker M D C; Lioliou G; Barnett A M

来源：Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment , 2018, 899: 106-114.

DOI：10.1016/j.nima.2018.05.032

• AlGaAs
• X-ray detector
• Spectroscopy
• Photodiode
• Array
• Semiconductor

A monolithic 2x2 square pixel Al0.2Ga0.8 As p(+)-i-n(+) mesa X-ray photodiode array (each photodiode area 200 mu m by 200 mu m, 3 mu m i layer) has been fabricated from material grown by MOVPE. The array was electrically characterised across the temperature range 100 degrees C to -20 degrees C. Each pixel's response to illumination with soft X-rays from an Fe-55 radioisotope X-ray source (Mn K alpha = 5.9 keV; Mn K beta = 6.49 keV) was investigated across the temperature range 30 degrees C to -20 degrees C. The best energy resolution (FWHM at 5.9 keV) achieved at 20 degrees C was 0.76 keV +/- 0.06 keV (with 30 V reverse bias applied to the detector). The measured energy resolution is the best so far reported for AlGaAs X-ray photodiodes at 20 degrees C. It is also the first time a small AlGaAs X-ray photodiode array has been demonstrated. Due to the temperature tolerance and the radiation hardness of AlGaAs, such detectors are expected to find utility in future space science missions exposed to intense radiation environments, for example missions to study the Jovian or Saturnian aurorae and high temperature planetary surfaces.

• 出版日期2018-8-11