Electronic device with patch antenna in packaging substrate
An electronic device includes a multilevel package substrate, a semiconductor die, and a package structure, the multilevel package substrate has first, second, and third levels including respective dielectric layers and conductive features, the first level including a first trace layer with an antenna and a first via layer with a portion of a ground wall laterally spaced outward from and surrounding the antenna, and the second level including a second trace layer having a ground plane connected to the ground wall, the semiconductor die attached to the first level of the multilevel package substrate, and the package structure including a molding compound enclosing the semiconductor die and extending on a side of the antenna, where the package structure mold compound maters and thickness can be tuned for improved performance.
1 . An electronic device, comprising:
a multilevel package substrate having a first level, a second level, and a third level, the first, second, and third levels each including a respective dielectric layer and patterned conductive features, the first, second, and third levels extending in respective first, second, and third planes of a first direction and an orthogonal second direction, the second level between the first and third levels along a third direction that is orthogonal to the first and second directions, the first level including a first trace layer with an antenna and a first via layer with a portion of a ground wall laterally spaced outward from and surrounding the antenna, and the second level including a second trace layer having a ground plane connected to the ground wall;
a semiconductor die attached to the first level of the multilevel package substrate; and
a package structure including a molding compound enclosing the semiconductor die and extending on a side of the antenna.
2 . The electronic device of claim 1 , wherein the first trace layer includes a second portion of the ground wall laterally spaced from and surrounding the antenna in the first plane.
3 . The electronic device of claim 1 , wherein the multilevel package substrate includes metal studs on first trace level for antenna and ground wall connections.
4 . The electronic device of claim 1 , wherein the multilevel package substrate includes conductive leads in the third level.
5 . The electronic device of claim 1 , wherein:
the semiconductor die is configured to operate the antenna at a wavelength λ; and
the molding compound has a thickness along the third direction of 0.125λ or more over the antenna.
6 . The electronic device of claim 5 , wherein the thickness of the molding compound is approximately 0.25λ.
7 . The electronic device of claim 5 , wherein the thickness of the molding compound is approximately λ/4+n λ/2, where n is a positive integer.
8 . The electronic device of claim 5 , wherein the thickness of the molding compound is λ/4+/−30%.
9 . The electronic device of claim 1 , wherein the molding compound has a loss tangent value less than 0.02.
10 . The electronic device of claim 9 , wherein the loss tangent value of the molding compound is approximately 0.001 or more and approximately 0.01 or less.
11 . A system, comprising:
a circuit board; and
an electronic device, comprising:
a multilevel package substrate having a first level, a second level, and a third level, the first, second, and third levels each including a respective dielectric layer and respective patterned conductive features, the first, second, and third levels extending in respective first, second, and third planes of a first direction and an orthogonal second direction, the second level between the first and third levels along a third direction that is orthogonal to the first and second directions, the first level including a first trace layer with an antenna and a first via layer with a portion of a ground wall laterally spaced outward from and surrounding the antenna, the second level including a second trace layer having a ground plane connected to the ground wall, and the multilevel package substrate having conductive leads coupled to the circuit board;
a semiconductor die attached to the first level of the multilevel package substrate; and
a package structure including a molding compound enclosing the semiconductor die and extending on a side of the antenna.
12 . The system of claim 11 , wherein the first trace layer includes a second portion of the ground wall laterally spaced from and surrounding the antenna in the first plane.
13 . The system of claim 11 , wherein:
the semiconductor die is configured to operate the antenna at a wavelength λ; and
the molding compound has a thickness along the third direction of 0.125λ or more over the antenna.
14 . The system of claim 11 , wherein the molding compound has a loss tangent value less than 0.02.
15 . A method of fabricating an electronic device, the method comprising:
fabricating a multilevel package substrate, including forming a first level, a second level, and a third level, the first, second, and third levels each including a respective dielectric layer and respective patterned conductive features, the second level between the first and third levels, the first level including a first trace layer with an antenna and a first via layer with a portion of a ground wall laterally spaced outward from and surrounding the antenna, and the second level including a second trace layer having a ground plane connected to the ground wall;
flip-chip attaching a semiconductor die to the first level of the multilevel package substrate; and
forming a package structure including a molding compound that encloses the die and extends on a side of the antenna.
16 . The method of claim 15 , wherein the first trace layer includes a second portion of the ground wall laterally spaced from and surrounding the antenna.
17 . The method of claim 15 , wherein:
the semiconductor die is configured to operate the antenna at a wavelength λ; and
the molding compound has a thickness of 0.125λ or more over the antenna.
18 . The method of claim 17 , wherein the thickness of the molding compound is approximately 0.25λ.
19 . The method of claim 17 , wherein the thickness of the molding compound is approximately λ/4+n λ/2, where n is a positive integer.
20 . The method of claim 15 , wherein the molding compound has a loss tangent value less than 0.02.