Advances on Radiation-Tolerant Geiger Photodiodes

The operation of nuclear instruments in high-radiation environments is critical for a myriad of applications, which include intense particle beams for future science experiments, in-situ measurements for emerging and advanced nuclear fuel cycles, or operation in a diverse range of environmental and harsh radiation conditions for military applications. A common tool used to measure ionizing radiation is scintillation materials, which produce a light pulse with an intensity proportional to the energy deposited, where a photodetector is used to measure the light pulse. The photomultiplier tube is a photodetector sensitive enough for scintillator readout, yet these devices are typically bulky, fragile, expensive, and vulnerable to magnetic fields. Though SiPMs, formed from an array of single photon avalanche photodiodes, or Geiger photodiodes (GPD), are replacing photomultiplier tubes, they are susceptible to radiation damage. This work discusses new technologies of GPDs consisting of GaAs and AlGaAsSb for operation in intense radiation and environmental conditions.