Tailoring Artificial Mode to Enable Cofired Integration of Shear‐type Piezoelectric Devices. Issue 17 (6th July 2020) - Yang, Jikun
Abstract: Low‐temperature cofired ceramic technology is the prerequisite for producing advanced integrated piezoelectric devices that enable modern micro‐electromechanical systems because of merits such as high level of compactness and ultralow drive voltage. However, piezoceramic structure with shear‐type outputs, as a most fundamental functional electronic element, has never been successfully fabricated into multilayer form by the cofired method for decades. Technical manufacture requirements of parallel applied electric fields and polarization are theoretically incompatible with intrinsically orthogonal orientations in naturally occurring shear modes. Herein, inspired by the philosophy of building metamaterial from identical unit cells, an artificial prototype device with distinctive patterned electrodes and arrayed piezoceramic subunits is designed and fabricated, which is proved to perfectly generate synthetic face shear deformation. At the same drive voltage, an enhanced shear‐type displacement output by over an order of magnitude is observed beyond previous d15 ‐mode bulk elements. Further results of guided wave‐based structural health monitoring and force sensing confirm that the methodology wipes out a tough piezoelectric technique barrier, and promises to fundamentally enlighten advances of integrated shear‐mode piezoelectric devices for augmented actuation, sensing, and transduction applications. Abstract : This work reports an ingenious metamaterial‐inspired methodology to first realize cofired manufacture of multilayer shear‐type piezoelectric devices, which is a long‐term challenge in piezoelectric techniques. The artificially prototype d36 ‐mode device shows enhanced shear‐type displacement output by over 20 times beyond previous d15 ‐mode bulk one at the same drive voltage, and leads to obviously augmented performance for actuation, sensing, and transduction applications.