Multifunction properties of GaAs and other III-V semi-insulating crystals could be expanded by the artificial decreasing of their electric response symmetry that could be transformed from piezo- into a pyroelectric class. Artificial pyroelectricity of III-V type semiconductors forms a basis for one-crystal pyroelectric sensor. The voltage sensitivity of GaAs (111)-cut is the similar to PZT pyroelectric ceramics, so GaAs wafer could be used as a thermal-to-electric transducer in a new microelectronic device named pyrotransistor. The last is uncooling far infrared (IR) detector based on MESFET technology
