一种体声波谐振器

Abstract

本实用新型公开了一种体声波谐振器。体声波谐振器包括：硅晶圆；二氧化硅层，位于硅晶圆的一侧；二氧化硅层设置有镂空结构；第一电极层；第一电极层、二氧化硅层的镂空结构和硅晶圆形成空腔结构；在第一电极层靠近硅晶圆的一侧设置有第一框架结构，第一框架结构包括朝向空腔结构的凸凹结构；压电层；第二电极层，在第二电极层上设置有第二框架结构，第二框架结构包括朝向远离硅晶圆一侧的凸凹结构。相比于仅设置第二框架结构，本实用新型又设置了第一框架结构，第一框架结构能够与第二框架结构相互配合，进一步抑制横向声波的泄露，将更多的能量限制在体声波谐振器器件内部，显著减少声波能量的发散。

Claims

1. A bulk acoustic wave resonator, characterized by, include: Silicon wafers; A silicon dioxide layer is located on one side of the silicon wafer; the silicon dioxide layer has a hollow structure. A first electrode layer is disposed on the side of the silicon dioxide layer away from the silicon wafer, and the first electrode layer, the hollow structure of the silicon dioxide layer, and the silicon wafer form a cavity structure; a first frame structure is disposed on the side of the first electrode layer close to the silicon wafer, and the first frame structure includes a convex and concave structure facing the cavity structure. A piezoelectric layer is disposed on the side of the first electrode layer away from the silicon wafer; A second electrode layer is disposed on the side of the piezoelectric layer away from the silicon wafer. A second frame structure is disposed on the second electrode layer, the second frame structure including a bump-and-concave structure facing away from the silicon wafer.

2. The bulk acoustic resonator of claim 1, wherein, The first electrode layer includes a first electrode structure and a second electrode structure. The vertical projection of the first electrode structure on the silicon wafer overlaps with the vertical projection of the cavity structure on the silicon wafer. The first frame structure is disposed on the first electrode structure. The second electrode layer includes a third electrode structure and a fourth electrode structure. The vertical projection of the fourth electrode structure on the silicon wafer overlaps with the vertical projection of the cavity structure on the silicon wafer. The second frame structure is disposed on the fourth electrode structure.

3. The bulk acoustic resonator of claim 1, wherein, The vertical projection of the first frame structure on the silicon wafer and the vertical projection of the second frame structure on the silicon wafer completely overlap, and the convex and concave structure surrounds the overlapping portion of the first electrode layer and the second electrode layer; the vertical projection of the first frame structure on the silicon wafer and the vertical projection of the second frame structure on the silicon wafer do not overlap at all; or the vertical projection of the first frame structure on the silicon wafer and the vertical projection of the second frame structure on the silicon wafer partially overlap.

4. The bulk acoustic resonator of claim 1, wherein, The first frame structure includes at least one of the said convex and concave structures, and the second frame structure includes at least one of the said convex and concave structures.

5. The bulk acoustic resonator of claim 2, wherein, Also includes: First through hole and second through hole; The first through hole is disposed on the fourth electrode structure, the first through hole penetrates the piezoelectric layer, a metal wire is disposed in the first through hole, and the first electrode structure is connected to the second electrode structure through the first through hole; The second through hole is disposed on the third electrode structure, the second through hole penetrates the piezoelectric layer, a metal wire is disposed in the second through hole, and the second electrode structure is connected to the first electrode structure through the second through hole.

Images