公开(公告)号：US20170099042A1

公开(公告)日：2017-04-06

申请号：US14954224

申请日：2015-11-30

Applicant: RF Micro Devices, Inc.

Inventor： Kurt G. Steiner ,  Curtiss Hella ,  Benjamin P. Abbott ,  Daniel Chesire ,  Chad Thompson ,  Alan S. Chen

IPC: H03H9/64

CPC classification number: H03H9/6489 ,  H03H3/04 ,  H03H3/10 ,  H03H9/02622 ,  H03H9/02834 ,  H03H9/02921 ,  H03H9/02929 ,  H03H9/02937 ,  H03H9/131 ,  H03H9/14541

Abstract: Embodiments of a Surface Acoustic Wave (SAW) device, or filter, and methods of fabrication thereof are disclosed. In some embodiments, the SAW filter comprises a piezoelectric substrate and an Interdigitated Transducer (IDT) on a surface of the piezoelectric substrate. The IDT includes multiple fingers, each comprising a metal stack. The SAW filter further includes a cap layer on a surface of the IDT opposite the piezoelectric substrate and on areas of the surface of the piezoelectric substrate exposed by the IDT. The cap layer has a thickness in a range of and including 10 to 500 Angstroms and a high electrical resistivity (and thus a low electrical conductivity). For instance, in some embodiments, the electrical resistivity of the cap layer is greater than 10 kilo-ohm meters (KΩ·m). The SAW filter further includes an oxide overcoat layer on a surface of the cap layer opposite the IDT and the piezoelectric substrate.

公开(公告)号：US09973169B2

公开(公告)日：2018-05-15

申请号：US14954224

申请日：2015-11-30

Applicant: RF Micro Devices, Inc.

Inventor： Kurt G. Steiner ,  Curtiss Hella ,  Benjamin P. Abbott ,  Daniel Chesire ,  Chad Thompson ,  Alan S. Chen

IPC: H03H9/64 ,  H03H3/10 ,  H03H9/145 ,  H03H9/02 ,  H03H3/04 ,  H03H9/13

CPC classification number: H03H9/6489 ,  H03H3/04 ,  H03H3/10 ,  H03H9/02622 ,  H03H9/02834 ,  H03H9/02921 ,  H03H9/02929 ,  H03H9/02937 ,  H03H9/131 ,  H03H9/14541

Abstract: Embodiments of a Surface Acoustic Wave (SAW) device, or filter, and methods of fabrication thereof are disclosed. In some embodiments, the SAW filter comprises a piezoelectric substrate and an Interdigitated Transducer (IDT) on a surface of the piezoelectric substrate. The IDT includes multiple fingers, each comprising a metal stack. The SAW filter further includes a cap layer on a surface of the IDT opposite the piezoelectric substrate and on areas of the surface of the piezoelectric substrate exposed by the IDT. The cap layer has a thickness in a range of and including 10 to 500 Angstroms and a high electrical resistivity (and thus a low electrical conductivity). For instance, in some embodiments, the electrical resistivity of the cap layer is greater than 10 kilo-ohm meters (KΩ·m). The SAW filter further includes an oxide overcoat layer on a surface of the cap layer opposite the IDT and the piezoelectric substrate.