Nano Ag sintering on Cu substrate assisted by self-assembled monolayers for high-temperature electronics packaging

Liu, Canyu; Liu, Allan; Su, Yuezeng; Zhou, Zhaoxia; Liu, Changqing

doi:10.1016/j.microrel.2021.114241

Cited by 7 publications

(2 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Subsequently, the samples were immersed in a solution containing 1-hexanethiol (C6, from Sigma-Aldrich, Darmstadt, Germany) diluted to a concentration of 1 mMol in isopropanol. In total, 4 mL of glacial acetic acid (99.7% from Wako) was added per liter of solution to remove any Cu oxide that formed during air exposure [ 20 , 30 ]. Finally, the samples were rinsed with isopropanol and dried using N 2 gas.…”

Section: Methodsmentioning

confidence: 99%

Cu-Cu Thermocompression Bonding with a Self-Assembled Monolayer as Oxidation Protection for 3D/2.5D System Integration

et al. 2023

View full text Add to dashboard Cite

Cu-Cu direct interconnects are highly desirable for the microelectronic industry as they allow for significant reductions in the size and spacing of microcontacts. The main challenge associated with using Cu is its tendency to rapidly oxidize in air. This research paper describes a method of Cu passivation using a self-assembled monolayer (SAM) to protect the surface against oxidation. However, this approach faces two main challenges: the degradation of the SAM at room temperature in the ambient atmosphere and the monolayer desorption technique prior to Cu-Cu bonding. In this paper, the systematic investigation of these challenges and their possible solutions are presented. The methods used in this study include thermocompression (TC) bonding, X-ray photoelectron spectroscopy (XPS), shear strength testing, scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX). The results indicate nearly no Cu oxidation (4 at.%) for samples with SAM passivation in contrast to the bare Cu surface (27 at.%) after the storage at −18 °C in a conventional freezer for three weeks. Significant improvement was observed in the TC bonding with SAM after storage. The mean shear strength of the passivated samples reached 65.5 MPa without storage. The average shear strength values before and after the storage tests were 43% greater for samples with SAM than for the bare Cu surface. In conclusion, this study shows that Cu-Cu bonding technology can be improved by using SAM as an oxidation inhibitor, leading to a higher interconnect quality.

show abstract

Section: Methodsmentioning

confidence: 99%

Cu-Cu Thermocompression Bonding with a Self-Assembled Monolayer as Oxidation Protection for 3D/2.5D System Integration

et al. 2023

View full text Add to dashboard Cite

show abstract

“…Micron silver flakes and silver nanoparticles have more free energy and need less external energy to initiate the fusion process allowing dieattach material sinter at a low temperature of <200 °C [8]. Die attachment by silver sintering at such low temperatures could relieve residual thermal mechanical stress and avoid chip damage [9].…”

Section: Introductionmentioning

confidence: 99%

Enhancing Semiconductor Package Reliability through Mechanical Property Optimization of Pressureless Sintering Die Attach Adhesives

Hong,

Xia,

Pang

et al. 2024

IMAPSource Proceedings

View full text Add to dashboard Cite

There is growing demand for high-power devices, wide bandgap SiC and GaN semiconductor materials in semiconductor market, and a drive to integrate die attach materials that can replace lead-containing solders. However, epoxy-based and solder materials face challenges to meet high thermal conductivity and survive elevated working temperatures. Pressure-assisted silver sintering has overcome these challenges, but downsides of pressure-assisted silver sintering are that it requires special equipment and for some applications, packages are unable to withstand the pressure required to facilitate sintering. Pressureless sintering materials could be processed using the same equipment as traditional die attach adhesives. It develops strong metal bonds to substrates, providing high thermal conductivity and withstanding high temperatures. However, compared to pressure-assisted sintering, pressureless materials may have difficulties to form a dense bondline structure if the formulation design is not optimized. Moreover, once the sintered structure is built during cure, further bondline reduction may induce additional stress. Therefore, it is critical that the pressureless sintering material’s mechanical properties are formulated to effectively manage stress and pass all reliability testing – especially for automotive packages. This paper will present the findings from a study that evaluated the impact of various formulation components – such as silver packing and resin chemistry – on the mechanical properties and interfacial bonding of pressureless sintering die attach adhesives. The effect on in-package reliability performance was also investigated to better understand material properties that can pass reliability testing while maintaining high thermal and electrical conductivity adhesive requirements.

show abstract

Temperature and thickness-dependent silver hillock generation mechanism and surface morphology nature of direct plated silver layers onto copper substrates

Kim,

Zhang

et al. 2024

Journal of Alloys and Compounds

View full text Add to dashboard Cite

Nano Ag sintering on Cu substrate assisted by self-assembled monolayers for high-temperature electronics packaging

Cited by 7 publications

References 13 publications

Cu-Cu Thermocompression Bonding with a Self-Assembled Monolayer as Oxidation Protection for 3D/2.5D System Integration

Cu-Cu Thermocompression Bonding with a Self-Assembled Monolayer as Oxidation Protection for 3D/2.5D System Integration

Enhancing Semiconductor Package Reliability through Mechanical Property Optimization of Pressureless Sintering Die Attach Adhesives

Temperature and thickness-dependent silver hillock generation mechanism and surface morphology nature of direct plated silver layers onto copper substrates

Contact Info

Product

Resources

About