美国科学家最近通过试验发现，压电陶瓷等智能材料的性能和反应随着尺寸的不同而大相径庭。薄膜状智能材料的压电性能和介电系数与其厚度密切相关。材料越薄，预期的反应就越小。 　　压电陶瓷通常用于压力传感器、麦克风和加速度计。薄膜状压电陶瓷一般用于微型机电装置（ MEM American scientists recently found through experiments that the performance and response of smart materials such as piezoelectric ceramics vary widely in size. The piezoelectric properties and dielectric constant of thin-film smart materials are closely related to their thickness. The thinner the material, the smaller the expected response. Piezoelectric ceramics are commonly used for pressure sensors, microphones and accelerometers. Thin-film piezoelectric ceramics are generally used in micro-electromechanical devices (MEM