A Review of Sintering-Bonding Technology Using Ag Nanoparticles for Electronic Packaging

Abstract

Metal nanoparticles (NPs) have attracted growing attention in recent years for electronic packaging applications. Ag NPs have emerged as a promising low-temperature bonding material owing to their unique characteristics. In this study, we mainly review our research progress on the interconnection of using polyol-based Ag NPs for electronic packaging. The synthesis, sintering-bonding process, bonding mechanism, and high-temperature joint properties of Ag NP pastes are investigated. The paste containing a high concentration of Ag NPs was prepared based on the polyol method and concentration. A nanoscale layer of organic components coated on the NPs prevents the coalescence of Ag NPs. The effects of organic components on the bondability of the Ag NP paste were studied. Compared to the aqueous-based Ag NP paste, the polyol-based Ag NP with the reduction of organic component can improve the bondability, and the coffee ring effect was successfully depressed due to the increased Marangoni flow. The sintering behaviors of Ag NPs during the bonding process were investigated using the classical sphere-to-sphere approach. The mechanical property of joints using this Ag paste was better than that using Pb95Sn5 solders after storage at high temperatures. The sintering–bonding technology using polyol-based Ag NPs was helpful to the low-temperature interconnection for electronic packaging applications.

Effectiveness of Oxygen during Sintering of Silver Thin Films Derived by Nanoparticle Ink

“…In addition, it should be noted that such a stage transition in oxygen was accomplished at a temperature below 250 °C, when the decomposition of PVP had not yet begun according to the thermal analysis results shown in Figure 2 . As reported by Yan et al [ 51 ], the organic dispersant in silver NP ink had an important influence on the sintering process, because it was found through FTIR that the carboxyl oxygen atoms of PVP interacted with silver NPs on the surface. When the temperature was low, the particles were encapsulated by PVP, and the sintering mechanism at this time depended on surface diffusion; when the temperature was raised to decompose the dispersant, the sintering process turned to volumetric diffusion.…”

“…The temperatures of the initiation of PVP decomposition were about 280 °C in oxygen and 400 °C in nitrogen, respectively, as shown in Figure 2 . As suggested in the related literature [ 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 ], the encapsulation of silver NPs by organic dispersants significantly affects the sintered morphology and consequently the properties of sintered silver thin films. Thus, it could be supposed that the breaching of the PVP dispersant capsulation of the silver NPs through enabling its decomposition is a prerequisite condition for the stage transition from particle coalescence to film densification, because the presence of PVP would limit the volumetric diffusion of silver NPs.…”

Recent Advances on Thermally Conductive Adhesive in Electronic Packaging: A Review

“…Metal nanoparticles (NPs) have recently gained popularity due to their unique properties such as low melting temperature and high diffusion coefficient [ 91 ]. Research has shown that epoxy conductive adhesives enhance their heat conductivity when integrated with metal fillers.…”

Low-Temperature Sintering of Ag Composite Pastes with Different Metal Organic Decomposition Additions

“…Ag nanoparticles are widely used as lead-free die attachments due to their relatively high conductivity, superior fatigue properties, and high melting point [ 9 , 10 , 11 ]. However, the high sintering temperature (~250 °C) and long sintering time (30~60 min) associated with their production limit their widespread application [ 12 ].…”