EP-4740246-A1 - COPPER POST DESIGN ON LAMINATE FOR IMPROVED PERFORMANCE AND RELIABILITY

Abstract

The present disclosure relates to a double-side molded module with copper post structures, which are formed by using a two-step plating process. The disclosed double-side molded module includes the copper post structures and a laminate panel that has a laminate body with a first surface and a second surface opposite the first surface, and capture pads on the second surface of the laminate body. The copper post structures include a number of lower copper posts formed over the capture pads, respectively, and a number of upper copper posts directly formed over the lower copper posts. At least one of the copper post structures includes a first lower copper post of the lower copper posts and two or more of the upper copper posts confined within the first lower copper post.

Inventors

• MORRIS, Thomas, Scott
• ORLOWSKI, John, August
• KO, Yong-Jae
• WILLIS, DON
• CALHOUN, Brian, Howard
• CARPENTER, Charles, E.

Assignees

• Qorvo US, Inc.

Dates

Publication Date

20260513

Application Date

20240701

Claims (20)

1. 1 . A double-side molded module comprising: • a laminate panel that includes a laminate body with a first surface and a second surface opposite the first surface, and capture pads on the second surface of the laminate body; and • a plurality of copper post structures formed on the capture pads, respectively, wherein: • the plurality of copper post structures includes a plurality of lower copper posts formed over the capture pads, respectively, and a plurality of upper copper posts directly formed over the plurality of lower copper posts; and • at least one of the plurality of copper post structures includes a first lower copper post of the plurality of lower copper posts and two or more of the plurality of upper copper posts confined within the first lower copper post.
2. 2. The double-side molded module of claim 1 wherein each of the plurality of upper copper posts has a same shape and a same size.
3. 3. The double-side molded module of claim 1 wherein the plurality of lower copper posts has one or more shapes consisting of circles, rectangles, squares, L-shapes, C-shapes, ovals, rings, open sided shapes, and closed sided shapes.
4. 4. The double-side molded module of claim 1 wherein: • each of the plurality of copper post structures has a thickness between 20 pm and 280 pm; • each of the plurality of lower copper posts has a thickness between 10 pm and 140 pm; and • each of the plurality of upper copper posts has a thickness between 10 pm and 140 pm.
5. 5. The double-side molded module of claim 1 wherein at least one of the plurality of copper post structures includes a second lower copper post of the plurality of lower copper posts and only one of the plurality of upper copper posts confined within the second lower copper post.
6. 6. The double-side molded module of claim 1 further comprising: • at least one first electronic component formed on the first surface of the laminate body; and • at least one second electronic component formed on the second surface of the laminate body and surrounded by the plurality of copper post structures.
7. 7. The double-side molded module of claim 6 further comprising a plurality of first pads on the first surface of the laminate body, and a plurality of second pads on the second surface of the laminate body and surrounded by the plurality of copper post structures, wherein: • the at least one first electronic component is formed on the plurality of first pads, and the at least one second electronic component is formed on the plurality of second pads; and • the at least one first electronic component and the at least one second electronic component are electrically connected to corresponding ones of the plurality of copper post structures.
8. 8. The double-side molded module of claim 7 wherein: • the at least one first electronic component is one or more of a group consisting of flip-chip dies and surface mounted devices (SMDs); and • the at least one second electronic component is one or more of a group consisting of flip-chip dies and SMDs.
9. 9. The double-side molded module of claim 6 further comprising: • a first mold compound formed over the first surface of the laminate body to completely cover the at least one first electronic component; and • a second mold compound formed over the second surface of the laminate body, wherein: • the second mold compound partially covers each of the plurality of copper post structures, such that a tip surface of each of the plurality of upper copper posts is exposed through the second mold compound; and • the second mold compound at least partially covers the at least one second electronic component.
10. 10. A communication device comprising: • a control system; • a baseband processor; • receive circuitry; and • transmit circuitry, wherein at least one or any combination of the control system, the baseband processor, the transmit circuitry, and the receive circuitry is implemented in a double-side molded module, which includes a laminate panel and a plurality of copper post structures, wherein: • the laminate panel includes a laminate body with a first surface and a second surface, and capture pads on the second surface of the laminate body; • each of the plurality of copper post structures is formed on a corresponding one of the capture pads; • the plurality of copper post structures includes a plurality of lower copper posts formed over the capture pads, respectively, and a plurality of upper copper posts directly formed over the plurality of lower copper posts; and • at least one of the plurality of copper post structures includes a first lower copper post of the plurality of lower copper posts and two or more of the plurality of upper copper posts confined within the first lower copper post.
11. 1 1. A method comprising: • providing an initial plating precursor having a laminate panel, a first plating resist, and a second plating resist, wherein: • the laminate panel includes a laminate body with a first surface and a second surface, and capture pads on the second surface of the laminate body; and • the first plating resist is formed over the first surface of the laminate body, and the second plating resist is formed over the second surface of the laminate body to encapsulate the capture pads; • selectively removing portions of the second plating resist to provide a plurality of lower plating holes, wherein each of the plurality of lower plating holes extends through the second plating resist to expose a corresponding one of the capture pads; • forming a plurality of lower copper posts in the plurality of lower plating holes, respectively, wherein each of the plurality of lower copper posts is connected to the corresponding one of the exposed capture pads; • applying a third plating resist over the second plating resist to provide a second plating precursor, wherein the third plating resist encapsulates each of the plurality of lower copper posts; and • selectively removing portions of the third plating resist to provide a plurality of upper plating holes, wherein: • each of the plurality of upper plating holes extends through the third plating resist to expose a corresponding one of the plurality of lower copper posts; and • two or more of the plurality of upper plating holes are formed over a first one of the plurality of lower copper posts.
12. 1 . The method of claim 11 wherein each of the plurality of upper plating holes has a same shape and a same size.
13. 13. The method of claim 11 wherein the plurality of lower copper posts has one or more shapes consisting of circles, rectangles, squares, L-shapes, C- shapes, ovals, rings, open sided shapes, and closed sided shapes.
14. 14. The method of claim 11 wherein the laminate panel further includes a seed metal film, wherein: • the capture pads are connected with each other by the seed metal film; and • forming the plurality of lower copper posts is provided by an electrolytic copper plating step, wherein the capture pads are coupled to a voltage source via the seed metal film and function as electrolytic plating seed pads to attract a plating material though the plurality of lower plating holes to form the plurality of lower copper posts.
15. 15. The method of claim 14 further comprising forming a plurality of upper copper posts in the plurality of upper plating holes, respectively, wherein: • each of the plurality of upper copper posts is connected to the corresponding one of the lower copper posts; • a plurality of copper post structures is composed of the plurality of upper copper posts and the plurality of lower copper posts; and • a first one of the plurality of copper post structures includes the first one of the plurality of lower copper posts and two or more of the plurality of upper copper posts confined within the first one of the plurality of lower copper posts.
16. 16. The method of claim 15 wherein: • each of the plurality of copper post structures has a thickness between 20 pm and 280 pm; • each of the plurality of lower copper posts has a thickness between 10 pm and 140 pm; and • each of the plurality of upper copper posts has a thickness between 10 pm and 140 pm.
17. 17. The method of claim 15 further comprising grinding the plurality of upper copper posts, wherein after the grinding, each of the plurality of copper post structures has a same height.
18. 18. The method of claim 15 wherein within the initial plating precursor, the laminate panel further includes first pads on the first surface of the laminate body and second pads on the second surface of the laminate body, wherein: • the capture pads and the second pads are connected with each other by the seed metal film; • the first plating resist formed over the first surface of the laminate body encapsulates the first pads; and • the second plating resist formed over the second surface of the laminate body resides over the seed metal film and encapsulates both the capture pads and the second pads.
19. 19. The method of claim 18 further comprising, after forming the plurality of upper copper posts, removing the first plating resist, the second plating resist, and the third plating resist, so as to expose the first pads on the first surface of the laminate body and to expose the second pads, the capture pads, and the seed metal film on the second surface of the laminate body.
20. 20. The method of claim 19 further comprising selectively removing portions of the seed metal film so as to separate each of the capture pads and each of the second pads.

Description

COPPER POST DESIGN ON LAMINATE FOR IMPROVED PERFORMANCE AND RELIABILITY Related Applications [0001] This application claims the benefit of provisional patent application serial number 63/511 ,949, filed July 5, 2023, and provisional patent application serial number 63/511 ,947, filed July 5, 2023, the disclosures of which are hereby incorporated herein by reference in their entireties. Field of the Disclosure [0002] The present disclosure relates to a double-side molded module with copper posts, and a method of fabricating the double-side molded module with the copper posts in a reliable manner without die cracks or component interconnect failures. In addition, the method of fabricating the double-side molded module can also increase copper mass without increasing a thickness of the double-side molded module by a two-step plating process, thereby improving module performance. Background [0003] With the popularity of portable consumer electronic products, such as smart phones, tablet computers, and so forth, double-sided assemblies are becoming more and more attractive in microelectronics devices to achieve electronics densification in a small footprint. [0004] However, a conventional double-side molded module, which utilizes Ball Grid Array (BGA), may result in a relatively large thickness of the final product and have limitations for input/output (I/O) density. It is because each solder ball of the BGA has a relatively large size (in both horizontal and vertical dimensions). In order to achieve a desired module performance, a thickness of a laminate substrate of the double-side molded module typically cannot be reduced. In some applications, to improve the double-side molded module’s performance, it is necessary to increase the thickness of the laminate substrate. The conventional double-side molded module with the BGA is limited to a decreased thickness of less than 0.7mm. In addition, the BGA is not superior for thermal dissipation, especially for high frequency and high-power applications. [0005] Accordingly, to accommodate the low-profile requirements for portable products and to enhance thermal and electrical performance, it is therefore an object of the present disclosure to provide a fabricating method for producing an improved double-side molded module with a reduced thickness or with increased copper mass without increasing the thickness. It is also desirable to fabricate the improved double-side molded module in a reliable manner without die cracks or component interconnect failures. [0006] The present disclosure relates to a double-side molded module with copper posts, and a method of fabricating the double-side molded module with the copper posts in a reliable manner without die cracks or component interconnect failures, in particular reducing height variation of the copper posts during fabrication of the double-side molded module. In addition, the method of fabricating the double-side molded module with the copper posts can also increase copper mass without increasing a thickness of the double-side molded module by a two-step plating process, thereby improving module performance. [0007] The disclosed method starts with providing a plating precursor, which includes a laminate panel with multiple active regions, a first plating resist, and a second plating resist. Herein, the laminate panel includes a laminate body, first pads on a first surface of the laminate body, and second pads on a second surface of the laminate body. Each of the first pads and each of the second pads are confined within a corresponding active region. The first plating resist is formed over the first surface of the laminate body to encapsulate the first pads, and the second plating resist is formed over the second surface of the laminate body to encapsulate the second pads. Next, portions of the second plating resist are selectively removed to provide a number of plating holes over certain ones of the second pads within each of the active regions, such that the certain ones of the second pads within each of the active regions are exposed through the plating holes, respectively. A number of copper posts are then formed in the plating holes, respectively, and each of the copper posts is connected to a corresponding one of the exposed second pads. The copper posts within each of the active regions are then planarized, such that each of the copper posts has an exposed horizontal surface through the second plating resist at a same plane. [0008] In one embodiment of the exemplary method, each of the copper posts has a height between 100 pm and 150 pm, and a diameter between 150 pm and 250 pm. [0009] In one embodiment of the exemplary method, the laminate panel further includes a seed metal film on the second surface of the laminate body connecting each of the second pads. [0010] In one embodiment of the exemplary method, the copper posts are formed by an electrolytic copper plating process. [0011] According to one embodiment