Page 26 - Chip Scale Review Sep Oct_2022-digital

Double-sided SiP for 5G and wearable applications

By David Wang, Mike Tsai, J. Y. Chen, YP Wang [Siliconware Precision Industries Co., Ltd]

T h e t r e n d i n m e d i c a l and thinner than single-sided SiP devices can be improved by selecting the proper

wearable devices – such as
reduce noise emission.
(ELK) material stress performance using
those used for collecting to improve power supply efficiency and strip grinding process. The extra low-k
medical data (e.g., heart rate detection, In this article, we report on tests a 3-point test methodology was also
electrocardiographs (ECGs), and various conducted on double-sided SiP structures studied so as to select the suitable double-
sensors) – requires small form factor to assess module-level warpage and sided SiP structure for the end product of
devices, smaller module sizes, multi-IC thermal dissipation performance. The the board-level manufacturing process.
and component integration, low power simulation and experiments included From an electrical integration point
consumption, and better heat dissipation. a design of experiments (DOE) on of view, a shorter signal transmission
The module size of the single-sided the molding process using different path is required to get good electrical
system in package (SiP) device no longer molding compounds. Regarding thermal performance (i.e., signal integrity [SI]
meets these next-generation requirements. performance, a solution was found that and power integrity [PI]) rather than a
The double-sided SiP structure, however, can improve performance 24~38%. The side by side flip-chip based structure. The
is expected to provide solutions for more double-sided SiP module can provide an performance verification was confirmed
diverse applications of wearable products advanced solution to address the module by simulation and measurement. The
in the future. The double-sided SiP size, cost, performance, and time-to- reliability testing verification includes
structure utilizes double-sided surface market requirements for internet of things temperature cycle testing (TCT), high-
mount technology (SMT) and dual-sided (IoT) devices and the wearables market. temperature storage life testing (HTSL)
molding to shrink the overall module The study described in this article will and unbiased highly accelerated stress
size. Furthermore, it can be reduced in also demonstrate that the package die testing (u-HAST) performed on the
size so that it is about 40~60% lighter strength of the double-sided SiP structure double-sided SiP structure.

Figure 1: Market volume and SiP application. SOURCE: 2021 Vol., 2026 Vol., ‘21~’26 CAGR, PRISMARK

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