title: Film bulk acoustic resonators integrated on arbitrary substrates using a polymer support layer.
abstract: The film bulk acoustic resonator (FBAR) is a widely-used MEMS device which can be used as a filter, or as a gravimetric sensor for biochemical or physical sensing. Current device architectures require the use of an acoustic mirror or a freestanding membrane and are fabricated as discrete components. A new architecture is demonstrated which permits fabrication and integration of FBARs on arbitrary substrates. Wave confinement is achieved by fabricating the resonator on a polyimide support layer. Results show when the polymer thickness is greater than a critical value, d, the FBARs have similar performance to devices using alternative architectures. For ZnO FBARs operating at 1.3-2.2 GHz, d is ~9 μm, and the devices have a Q-factor of 470, comparable to 493 for the membrane architecture devices. The polymer support makes the resonators insensitive to the underlying substrate. Yields over 95% have been achieved on roughened silicon, copper and glass.
authors.affiliation: Department of Information Science and Electronic Engineering, Zhejiang University and Cyrus Tang Center for Sensor Materials and Applications, Zhejiang University, Hangzhou 310027, China.
authors.forename: Guohao
authors.initials: G
authors.lastname: Chen
authors.affiliation: Department of Information Science and Electronic Engineering, Zhejiang University and Cyrus Tang Center for Sensor Materials and Applications, Zhejiang University, Hangzhou 310027, China.
authors.forename: Xinru
authors.initials: X
authors.lastname: Zhao
authors.affiliation: Department of Information Science and Electronic Engineering, Zhejiang University and Cyrus Tang Center for Sensor Materials and Applications, Zhejiang University, Hangzhou 310027, China.
authors.forename: Xiaozhi
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Information Science and Electronic Engineering, Zhejiang University and Cyrus Tang Center for Sensor Materials and Applications, Zhejiang University, Hangzhou 310027, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Jin
authors.affiliation: College of Computer Science, Zhejiang University, Hangzhou. 310027, China.
authors.forename: Shijian
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Information Science and Electronic Engineering, Zhejiang University and Cyrus Tang Center for Sensor Materials and Applications, Zhejiang University, Hangzhou 310027, China.
authors.forename: Shurong
authors.initials: S
authors.lastname: Dong
authors.affiliation: Electrical Engineering Division, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0FA U.K.
authors.forename: A J
authors.initials: AJ
authors.lastname: Flewitt
authors.affiliation: Electrical Engineering Division, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0FA U.K.
authors.forename: W I
authors.initials: WI
authors.lastname: Milne
authors.affiliation: 1] Department of Information Science and Electronic Engineering, Zhejiang University and Cyrus Tang Center for Sensor Materials and Applications, Zhejiang University, Hangzhou 310027, China [2] Institute of Renewable Energy and Environmental Technologies, Bolton University, Deane Road, Bolton BL3 5AB, UK.
authors.forename: J K
authors.initials: JK
authors.lastname: Luo
references.citation: Lab Chip. 2012 Jan 7;12(1):29-44
references.pmid: 22045252
references.citation: IEEE Trans Ultrason Ferroelectr Freq Control. 2011 Nov;58(11):2438-45
references.pmid: 22083776
references.citation: Sci Rep. 2013;3:2140
references.pmid: 23828169