ABSTRACT
Semiconductor detectors are solid-state devices that operate essentially like ionization chambers. The charge carriers in semiconductors are not electrons and ions, as in the gasfilled detectors, but electrons and "holes". At present, the most successful semiconductor detectors are made of silicon and germanium. The properties of semiconductors are discussed next, with special emphasis given to the properties of silicon and germanium. In most cases, controlled amounts of impurities are introduced purposely by a process called doping, which increases the conductivity of the material by orders of magnitude. In semiconductor detectors, the electric field is established by a process more complicated than in gas-filled detectors, a process that depends on the properties of n- and p-type semiconductors. There is a great incentive to develop semiconductor detectors that can be stored and operated at room temperature. Electrons and photons cause negligible radiation damage compared to charged particles and neutrons.
