LAUSR

LLE Review, Volume 157 15 Volume-type radiation detectors are devices that collect charged particles, such as electrons, produced by photon interaction with the detector material, typically a single crystal. In the case of highly energetic x-ray radiation photons, they interact with matter through three main mechanisms: the photoelectric effect, the Compton effect, and electron–positron pair production. The photoelectric effect is by far the most dominant effect among them because Compton-scattered photons, as well as high-energy gammas from electron–pair annihilations, typically escape from the detection volume and their energy cannot be collected. Photoconductive devices are, in fact, the most popular solid-state radiation detectors since they can often operate at room temperature, cover the spectral range up to hard x rays and even c rays, and are easy to design and fabricate.