Reliability Performance of S-Connect Module (Bridge Technology) for Heterogeneous Integration Packaging

Bridge technology is a promising heterogeneous integration (HI) solution for application-specific integrated circuits (ASICs) and high bandwidth memory (HBM). The bridge dies provide localized communications among the multiple system on chips (SoCs) in a single package. In Amkor's bridge technology, S-Connect provides die-to-die connections with fine pitch [1]. Prototype S-Connect technology was first reported in 2021 with a chip-first process. It used a double-side soldering process to connect an ASIC dummy to the bridge die. This paper presents recent work on a chip-last S-Connect with up to 3x reticle-sized modules. Two types of test vehicles were fabricated: 1) 1x reticle-sized module,
$32.8 \ \mathrm{x} \ 25.6$
mm
²
(1 ASIC and 2 HBM dummies) with 2 bridges and 2) 3x reticle-sized module,
$53.5 \ \mathrm{x} \ 45.4$
mm
²
(2 ASIC and 8 HBM dummies) with 10 bridges. Less than 100
$\mu \mathrm{m}$
of warpage was controlled by the epoxy mold compound selections with better results in the module attach process. In addition, the effect of die thickness on the module warpage was analyzed. After the module assembly process, good reliability performance was confirmed with moisture resistance testing level 4 (MRTL4), unbiased highly accelerated stress test (UHAST), thermal cycling condition B (TCB), and high temperature storage (HTS) tests. The results show that the chip-last S-Connect can be an advanced package solution for high-end applications.