Resonator with multilayer protruding structure, manufacturing method thereof, filter and electronic device

Abstract

The present invention relates to a bulk acoustic wave resonator, and the resonator comprises a substrate; an acoustic mirror; a bottom electrode disposed over the substrate; a top electrode facing thebottom electrode and having an electrode connection portion; a piezoelectric layer which is arranged above the bottom electrode and between the bottom electrode and the top electrode, wherein the edge of the top electrode is provided with at least a first protruding structure and a second protruding structure which are stacked in the thickness direction of the substrate, the first protruding structure is arranged on the top electrode, and the second protruding structure is arranged on the first protruding structure; the first projection structure has a first width, the second projection structure has a second width, and a ratio of the first width to the second width is in a range of 7: 1 to 9: 7. The invention further relates to a filter and an electronic device with the filter. The invention also relates to a manufacturing method of the bulk acoustic wave resonator, and the method comprises the steps: selecting the first width of the first protruding structure and the second width ofthe second protruding structure, and enabling the ratio of the first width to the second width to be in a range from 7: 1 to 9: 7.

Description

technical field [0001] Embodiments of the present invention relate to the field of semiconductors, and in particular to a bulk acoustic wave resonator and a manufacturing method thereof, a filter with the resonator, and an electronic device with the filter. Background technique [0002] Figure 5A The middle is the top view of the bulk acoustic wave resonator in the prior art, Figure 5B for along Figure 5A Schematic diagram of the cross-sectional structure taken along line A1-A2 in . exist Figure 5A and 5B In , the structure corresponding to the reference signs is as follows: [0003] 10: base [0004] 20: Acoustic mirror, in this example is a cavity, Bragg reflection layer or other equivalent sound wave reflection structure can also be used [0005] 30: bottom electrode [0006] 40: Piezoelectric film (piezoelectric layer) [0007] 50: top electrode [0008] 60: Top electrode pin [0009] AR: Effective Acoustic Area (Acoustoelectric Coupling Area) [0010] Figu...

AI Technical Summary

Problems solved by technology

[0014] Figure 5C and Figure 5D The protruding structure in has the disadvantages of insufficient ability to reflect sound waves and the sensitivity of sound wave reflection performance to size

Images