Pressureless Bonding by Micro-Sized Silver Particle Paste for High-Temperature Electronic Packaging

Abstract

Lead-free bonding in high-temperature electronic components is desirable for realizing eco-friendly technology. A pressureless process is more appropriate for electronic packaging because it enables a more automated manufacturing process and avoids any potential damage caused by application of pressure. Recently, Ag nanoparticles were used without pressure to join materials for high-temperature electronic applications. In this study, a Ag paste of micro-sized particles was proposed for electroless nickel immersion gold (ENIG) nished Cu pressureless bonding owing to its advantages of both cost effectiveness and easy manufacturing process compared to Ag nanoparticle paste. The micro-sized Ag paste was composed of both chestnut-burr-like (CBL) and spherical particles. The weight ratios of CBL to spherical particles were 10:0, 7:3, and 5:5. The bonding process was carried out at 573 K for 60 min in a nitrogen atmosphere. The experimental results showed that all of the sintered layers had an open porous structure. ENIG-nished Cu joint using the Ag paste of the 5:5 weight ratio exhibited the shear strength of 18.6 MPa, which is comparable to that of a conventional Pb-5Sn joint.

Low Temperature Sintered Silver Nanoflake Paste for Power Device Packaging and Its Anisotropic Sintering Mechanism

“…Normally, silver pastes containing spherical or flaky silver particles have been applied in the manufacturing of sintered silver joints with remarkable thermal conductivity and mechanical strength. , Many researchers have investigated the influence of silver filler morphology on sintered joints during and after the sintering process. − For example, Chen and co-workers found that the sintered silver joints derived from micron ball-milling silver flake paste exhibited a higher shear strength than that derived from nano, submicro, and micron silver particle paste . Furthermore, the same conclusion was drawn by Yeom and co-workers after comparing the shear strength of two types of sintered joints derived from spherical silver particle paste and ball-milled silver flake paste .…”

Prediction of Electrical Resistance with Conductive Sewing Patterns by Combining Artificial Neural Networks and Multiple Linear Regressions

“…Additionally, when used for power transmission, it has the potential to enable designs that optimize power efficiency. Using a scanning electron microscope (SEM), specifically the ZEISS Gemini SEM 300 from Oberkochen, Germany, we observed the surface of the conductive yarn coated with silver paste [32]. As can be seen in Figure 2, it exhibited a structure similar to the SEM image of silver paste coating.…”

Effect of compression pressure on strength of low-temperature sinter bonding produced using silver formate

“…Thus far, sinter bonding using silver (Ag) leads to fair processability at 200-300°C, even with microsized Ag or under pressureless conditions, and the mechanical reliability at high temperature [1][2][3][4][5][6][7]. However, a long bonding time of several tens of minutes is considered a real obstacle in providing mass productivity in the die-bonding of power devices.…”