Intelligent sensors for the next century

Abstract

Functional ceramics have become a news stage with the concept that different kinds of materials, no matter they are organic or inorganic with different functional effects, can be composed together to find a new material by multilayer thin film technologies. In this paper the design of new creative sensors, devices and system is proposed, which is based on: (1) Variation of spontaneous polarization Ps which can be induced or attended to maximum change during phase transformation; (2) Functional thin film materials which can be induced phase transitions by applied stress, temperature or electric field and these exhibit extraordinary piezoelectric, pyroelectric, electrostrictive, electro-optic, etc. and field effect properties in comparison with bulk materials so far existed; (3) Composite of these effects through thin film integrated technology to design new intelligent sensors; (4) Connecting equivalent circuits of functional elements, devices and electronic circuits to design new intelligent systems. As an example, a pyroelectric voltage transformer was introduced. The principle demonstration and experimental results are discussed.