Acoustic resonator package
An acoustic resonator package includes: a substrate; an acoustic resonator disposed on the substrate; a cap disposed on the substrate and the acoustic resonator; and a bonding portion bonding the substrate and the cap to each other, wherein the cap includes a trench formed around the bonding portion and a protective layer covering a surface of the trench in the cap, and wherein a portion of the bonding portion fills at least a portion of the trench.
1. An acoustic resonator package, comprising:
a substrate;
an acoustic resonator disposed on the substrate;
a cap disposed on the substrate and the acoustic resonator; and
a bonding portion bonding the substrate and the cap to each other,
wherein the cap comprises a trench formed around the bonding portion and a protective layer covering a surface of the trench in the cap, and
wherein a portion of the bonding portion fills at least a portion of the trench.
2. The acoustic resonator package of claim 1 , wherein the cap further comprises a central portion accommodating the acoustic resonator, and an outer portion disposed outwardly of the central portion and connected to the bonding portion, and
wherein the outer portion has a thickness greater than a thickness of the central portion.
3. The acoustic resonator package of claim 2 , wherein a ratio of a depth of the trench to a width of the trench is in a range of 1 to 30.
4. The acoustic resonator package of claim 2 , wherein the trench is formed in the outer portion.
5. The acoustic resonator package of claim 4 , wherein a difference in thicknesses between the outer portion and the central portion is greater than a depth of the trench.
6. The acoustic resonator package of claim 4 , wherein the protective layer is not formed on regions of the outer portion other than the trench.
7. The acoustic resonator package of claim 4 , wherein the protective layer is formed on an entire surface of the cap except for a region of the surface of the cap in contact with the bonding portion.
8. The acoustic resonator package of claim 1 , wherein an inner wall of the trench has a wavy shape.
9. The acoustic resonator package of claim 1 , wherein the protective layer is a self-assembled monolayer.
10. The acoustic resonator package of claim 1 , wherein the protective layer is formed of a material including a fluorocarbon group.
11. The acoustic resonator package of claim 10 , wherein the protective layer has a thickness of 0.1 nm to 10 nm.
12. The acoustic resonator package of claim 1 , wherein the protective layer is formed of a material including a silane group.
13. The acoustic resonator package of claim 12 , wherein the protective layer has a thickness of 10 nm to 50 nm.
14. The acoustic resonator package of claim 1 , wherein the bonding portion comprises an alloy.
15. The acoustic resonator package of claim 14 , wherein the alloy comprises at least two selected from the group consisting of (Au), tin (Sn), aluminum (Al), silicon (Si), and germanium (Ge).
16. The acoustic resonator package of claim 15 , wherein the alloy comprises one or more eutectic alloys selected from the group consisting Au-Sn, Cu-Sn, and Al-Ge.
17. The acoustic resonator package of claim 14 , wherein the bonding portion further comprises an insulating material that is a same material as a material forming the protective layer.