Matsushima Tomoaki, Xiong Sibei, Kawada Hiroshi, Yamanaka Hiroshi, Muralt Paul
New Product & Technologies Development Department, Matsushita Electric Works Ltd., Osaka, Japan.
IEEE Trans Ultrason Ferroelectr Freq Control. 2007 Dec;54(12):2439-45. doi: 10.1109/TUFFC.2007.557.
A highly sensitive piezoelectric ultrasonic micro-sensor with a grooved multilayer membrane was developed by a Si-based MEMS technique. The groove was located at one-quarter of the distance away from the edge of the membrane and opened into piezoelectric layer. The piezoelectric layer Pb(Zr,Ti)O(3) (PZT) was 2.2 microm thick and was prepared by a sol-gel method. The prepared PZT film was pure perovskite and showed a highly (100) textured structure. The sensitivity of the fabricated piezoelectric ultrasonic sensor without the groove structure was 100 microV/Pa. In comparison, the sensitivity of the ultrasonic sensor with the groove structure was about 500 microV/Pa, which is 5 times that without the groove structure. The diaphragm having grooves showed a corrugate-like structure that was formed by residual stress. The high sensitivity of the membrane with the grooved diaphragm is considered to relate to the corrugate-like structure.
通过基于硅的微机电系统(MEMS)技术开发了一种具有带凹槽多层膜的高灵敏度压电超声微传感器。该凹槽位于距膜边缘四分之一距离处,并通向压电层。压电层Pb(Zr,Ti)O(3)(PZT)厚度为2.2微米,采用溶胶-凝胶法制备。制备的PZT薄膜为纯钙钛矿结构,并呈现出高度(100)织构化结构。所制备的无凹槽结构的压电超声传感器的灵敏度为100微伏/帕。相比之下,具有凹槽结构的超声传感器的灵敏度约为500微伏/帕,是无凹槽结构传感器的5倍。具有凹槽的膜片呈现出由残余应力形成的波纹状结构。具有带凹槽膜片的膜的高灵敏度被认为与波纹状结构有关。