Self-shielded acoustic wave device package
A packaged acoustic wave component has an acoustic wave device mounted on a device substrate and a cap substrate spaced above the device substrate. The packaged acoustic wave component also has a shield structure including a metal plate disposed on a bottom surface of the cap substrate that faces the device substrate, the metal plate being spaced above the acoustic wave device, and a peripheral metal wall attached to the metal plate that extends to the device substrate. The shield structure encloses and electrically shields the acoustic wave device.
1 . A packaged acoustic wave component comprising:
an acoustic wave device mounted on a device substrate;
a planar cap substrate spaced above the device substrate; and
a shield structure including a metal plate disposed on a bottom surface of the planar cap substrate that faces the device substrate, an entirety of the planar cap substrate being axially above the metal plate, the metal plate being spaced above the acoustic wave device, and the shield structure further including a peripheral metal wall attached to the metal plate that extends from the metal plate to the device substrate, at least a portion of the peripheral metal wall being a monolithic, seamless piece with, and of a same material as, the metal plate, the at least a portion of the peripheral metal wall and the metal plate being made with a process for making the planar cap substrate, the peripheral metal wall attached to the device substrate, a cavity between the device substrate and the metal plate and bounded by the peripheral metal wall being under vacuum, the shield structure enclosing and electrically shielding the acoustic wave device.
2 . The packaged acoustic wave component of claim 1 wherein the metal plate is planar and extends substantially along a plane parallel to the bottom surface of the cap substrate, the metal plate including one or more metal layers.
3 . The packaged acoustic wave component of claim 1 wherein the acoustic wave device is a bulk acoustic wave device.
4 . The packaged acoustic wave component of claim 1 wherein the peripheral metal wall includes a first portion of a first material that is attached to the device substrate and a second portion of a second material that is attached to the metal plate, the second material being different than the first material.
5 . The packaged acoustic wave component of claim 4 wherein the peripheral metal wall includes a third portion of a third material different than the first material and the second material, the third portion interposed between the first portion and the second portion.
6 . The packaged acoustic wave component of claim 4 wherein a length of the first portion is greater than a length of the second portion.
7 . The packaged acoustic wave component of claim 4 wherein a width of the first portion is greater than a width of the second portion.
8 . The packaged acoustic wave component of claim 4 , wherein the first portion includes gold, the second portion includes copper, and the metal plate includes copper.
9 . The packaged acoustic wave component of claim 1 wherein the device substrate has a higher resistance than the cap substrate.
10 . The packaged acoustic wave component of claim 1 wherein the metal plate has a thickness of approximately 5 um.
11 . A radio frequency module comprising:
a package substrate;
a packaged acoustic wave component including an acoustic wave device mounted on a device substrate, a planar cap substrate spaced above the device substrate, and a shield structure including a metal plate disposed on a bottom surface of the planar cap substrate that faces the device substrate, an entirety of the planar cap substrate being axially above the metal plate, the metal plate being spaced above the acoustic wave device, and a peripheral metal wall attached to the metal plate that extends from the metal plate to the device substrate, at least a portion of the peripheral metal wall being a monolithic, seamless piece with, and of a same material as, the metal plate, the peripheral metal wall attached to the device substrate, the at least a portion of the peripheral metal wall and the metal plate being made with the process for making the planar cap substrate, a cavity between the device substrate and the metal plate and bounded by the peripheral metal wall being under vacuum, the shield structure enclosing and electrically shielding the acoustic wave device; and
additional circuitry, the packaged acoustic wave component and additional circuitry disposed on the package substrate.
12 . The radio frequency module of claim 11 wherein the metal plate has a thickness of approximately 5 um.
13 . The radio frequency module of claim 11 wherein the acoustic wave device is a bulk acoustic wave device.
14 . The radio frequency module of claim 11 wherein the peripheral metal wall includes a first portion of a first material that is attached to the device substrate and a second portion of a second material that is attached to the metal plate, the second material being different than the first material.
15 . The radio frequency module of claim 14 wherein the peripheral metal wall includes a third portion of a third material different than the first material and the second material, the third portion interposed between the first portion and the second portion.
16 . The radio frequency module of claim 14 , wherein the first portion includes gold, the second portion includes copper, and the metal plate includes copper.
17 . A wireless communication device comprising:
an antenna; and
a front end module including one or more packaged acoustic wave components configured to filter a radio frequency signal associated with the antenna, each packaged acoustic wave component including an acoustic wave device mounted on a device substrate, a planar cap substrate spaced above the device substrate, and a shield structure including a metal plate disposed on a bottom surface of the planar cap substrate that faces the device substrate, an entirety of the planar cap substrate being axially above the metal plate, the metal plate being spaced above the acoustic wave device, and a peripheral metal wall attached to the metal plate that extends from the metal plate to the device substrate, at least a portion of the peripheral metal wall being a monolithic, seamless piece with, and of a same material as, the metal plate, the peripheral metal wall attached to the device substrate, the at least a portion of the peripheral metal wall and the metal plate being made with the process for making the planar cap substrate, a cavity between the device substrate and the metal plate and bounded by the peripheral metal wall being under vacuum, the shield structure enclosing and electrically shielding the acoustic wave device.
18 . The wireless communication device of claim 17 wherein the metal plate has a thickness of approximately 5 um.
19 . The wireless communication device of claim 17 wherein the peripheral metal wall includes a first portion of a first material that is attached to the device substrate and a second portion of a second material that is attached to the metal plate, the second material being different than the first material.
20 . The wireless communication device of claim 19 wherein the peripheral metal wall includes a third portion of a third material different than the first material and the second material, the third portion interposed between the first portion and the second portion.