Abstract. One of important problems of recent electronics is non-cooled pyroelectric and piezoelectric sensors. They are realized usually in a hybrid integrated chip where thousands of ferroelectric ceramic elements are integrated with transistor matrix. Reported research work is devoted to the possibility of realization of one-crystal pyroelectric sensor. We revealed new effect of symmetry decrease that is used as a basis to develop one-crystal pyroelectric or piezoelectric sensor array using III-V crystals. In feasible sensor devices, the transducer, the amplifier and read-out electronics would be the various parts of one crystal chip. Voltage sensitivity of semi-insulating GaAs-type temperature sensor is the same as one of PZT pyroelectric ceramics. However, proposed device will be fully made from GaAs and related crystal layers by the standard in the micro-electronics technology
Keywords: gallium arsenide, piezoelectric, pyroelectric, membrane, FET.