Fabrication and Microstructural Study of Pressure-Assisted Nano-Silver Lap-Shear Joints for Power Electronics Packaging

International Journal of Mechanical Engineering

© 2026 by SSRG - IJME Journal

Volume 13 Issue 1

Year of Publication : 2026

Authors : Phuoc-Thanh Tran, Quang-Bang Tao, Van-Trung Pham

10.14445/23488360/IJME-V13I1P105

How to Cite?

Phuoc-Thanh Tran, Quang-Bang Tao, Van-Trung Pham, "Fabrication and Microstructural Study of Pressure-Assisted Nano-Silver Lap-Shear Joints for Power Electronics Packaging," SSRG International Journal of Mechanical Engineering, vol. 13,  no. 1, pp. 55-60, 2026. Crossref, https://doi.org/10.14445/23488360/IJME-V13I1P105

Abstract:

High-temperature power electronics place demanding requirements on interconnect reliability, yet most existing reports focus on either pressure or bondline thickness when evaluating nano-silver joints. Systematic data combining both factors, particularly in a controlled lap-shear configuration, remains limited. In this work, nano-silver joints were fabricated using a laboratory-built sintering stage capable of independent control of temperature (±3 °C), pressure (±0.05 MPa), and bondline spacing (±3 μm). A commercial nano-Ag paste was sintered at 280 °C under pressures of 1.0–1.5 MPa with target bondline thicknesses of 50, 70, and 100 μm. SEM observations showed continuous neck formation, uniform particle coalescence, and no visible cracking at the Ag–Cu interface. To verify that the joints were mechanically sound before entering a larger study, several preliminary lap-shear tests were performed using a custom shear fixture with high-resolution load and displacement measurement. Under quasi-static loading (strain rate ~ 1×10⁻⁴ s⁻¹, 25 °C), the joints produced strengths in the range of approximately 15–28 MPa depending on pressure and thickness, consistent with expected values for early-stage sintered Ag layers. These results confirm that the custom sintering setup can repeatedly produce well-bonded joints with stable morphology and predictable mechanical response, providing a reliable basis for subsequent detailed mechanical characterization. This work is among the few studies that simultaneously regulate temperature, pressure, and bondline thickness in a controlled lap-shear configuration.

Keywords:

Nano-silver sintering, Lap-shear joints, Bondline thickness control, Pressure-assisted fabrication, High-temperature interconnects, Microstructural characterization.

References:

[1] Norliza Ismail et al., “A Review of Extreme Condition Effects on Solder Joint Reliability: Understanding Failure Mechanisms,” Defence Technology, vol. 41, pp. 134-158, 2024.
[CrossRef] [Google Scholar] [Publisher Link]
[2] M. Lederer, A. Betzwar Kotas, and G. Khatibi, “A Lifetime Assessment and Prediction Method for Large Area Solder Joints,” Microelectronics Reliability, vol. 114, pp. 1-7, 2020.
[CrossRef] [Google Scholar] [Publisher Link]
[3] Qilong Guan et al., “Research Progress on the Solder Joint Reliability of Electronics Using in Deep Space Exploration,” Chinese Journal of Mechanical Engineering, vol. 36, no. 1, pp. 1-13, 2023.
[CrossRef] [Google Scholar] [Publisher Link]
[4] Kathlene N. Reeve et al., “Advances in Pb-Free Solder Microstructure Control and Interconnect Design,” Journal of Phase Equilibria and Diffusion, vol. 37, no. 4, pp. 369-386, 2016.
[CrossRef] [Google Scholar] [Publisher Link]
[5] R. Darveaux, “Effect of Simulation Methodology on Solder Joint Crack Growth Correlation,” 2000 Proceedings. 50th Electronic Components and Technology Conference (Cat. No.00CH37070), Las Vegas, NV, USA, pp. 1048-1058, 2000.
[CrossRef] [Google Scholar] [Publisher Link]
[6] Hyejun Kang, Ashutosh Sharma, and Jae Pil Jung, “Recent Progress in Transient Liquid Phase and Wire Bonding Technologies for Power Electronics,” Metals, vol. 10, no. 7, pp. 1-21, 2020.
[CrossRef] [Google Scholar] [Publisher Link]
[7] Omid Mokhtari, “A review: Formation of Voids in Solder Joint During the Transient Liquid Phase Bonding Process - Causes and Solutions,” Microelectronics Reliability, vol. 98, pp. 95-105, 2019.
[CrossRef] [Google Scholar] [Publisher Link]
[8] Junhyuk Son et al., “Thermal Reliability of Cu Sintering Joints for High-Temperature Die Attach,” Microelectronics Reliability, vol. 147, 2023.
[CrossRef] [Google Scholar] [Publisher Link]
[9] He Diao et al., “Study on the Interfacial Reactions for Ag/Sn/Cu TLP During Transient Liquid Phase Soldering Process,” Journal of Materials Science: Materials in Electronics, vol. 36, no. 5, 2025.
[CrossRef] [Google Scholar] [Publisher Link]
[10] H. Zhang, and K. Suganuma, Sintered Silver for LED Applications, Die-Attach Materials for High Temperature Applications in Microelectronics Packaging, Springer, Cham, pp. 35-65, 2019.
[CrossRef] [Google Scholar] [Publisher Link]
[11] Zhongqing Zhang et al., “Research on Sintering Process and Thermal Conductivity of Hybrid Nanosilver Solder Paste based on Molecular Dynamics Simulation,” Microelectronics Reliability, vol. 126, 2021.
[CrossRef] [Google Scholar] [Publisher Link]
[12] Hongqiang Zhang et al., “Microstructural and Mechanical Evolution of Silver Sintering Die Attach for Sic Power Devices During High Temperature Applications,” Journal of Alloys and Compounds, vol. 774, pp. 487-494, 2019.
[CrossRef] [Google Scholar] [Publisher Link]
[13] Yansong Tan, Xin Li, and Xu Chen, “Fatigue and Dwell-Fatigue Behavior of Nano-Silver Sintered Lap-Shear Joint at Elevated Temperature,” Microelectronics Reliability, vol. 54, no. 3, pp. 648-653, 2014.
[CrossRef] [Google Scholar] [Publisher Link]
[14] Hyeong-Woo Kang, and Jae Pil Jung, “Recent Sinter-Bonding Technology of Power Semiconductor Using Silver Particles,” Journal of Welding and Joining, vol. 43, no. 2, pp. 119-127, 2025.
[CrossRef] [Google Scholar] [Publisher Link]
[15] Keisuke Wakamoto, and Takahiro Namazu, “Mechanical Characterization of Sintered Silver Materials for Power Device Packaging: A Review,” Energies, vol. 17, no. 16, pp. 1-22, 2024.
[CrossRef] [Google Scholar] [Publisher Link]
[16] Chuantong Chen et al., “Development of SiC Power Module Structure by Micron-Sized Ag-Paste Sinter Joining on Both Die and Heatsink to Low-Thermal-Resistance and Superior Power Cycling Reliability,” IEEE Transactions on Power Electronics, vol. 39, no. 9, pp. 10638-10648, 2024.
[CrossRef] [Google Scholar] [Publisher Link]
[17] Meiyu Wang et al., “Characterization of Multiple Commercial Sintered-Silver Pastes as Die Attachment for Power Electronics Packaging: Materials, Processing, and Properties,” IEEE Journal of Emerging and Selected Topics in Power Electronics, vol. 13, no. 1, pp. 892-903, 2025.
[CrossRef] [Google Scholar] [Publisher Link]
[18] R. Khazaka, L. Mendizabal, and D. Henry, “Review on Joint Shear Strength of Nano-Silver Paste and its Long-Term High-Temperature Reliability,” Journal of Electronic Materials, vol. 43, no. 7, pp. 2459-2466, 2014.
[CrossRef] [Google Scholar] [Publisher Link]
[19] Lihua Gao et al., “Microstructure and Bonding Strength of Low-Temperature Sintered Ag/Nano-Ag Films/Ag Joints,” Metals, vol. 13, no. 11, pp. 1-12, 2023.
[CrossRef] [Google Scholar] [Publisher Link]
[20] Cheng Qian et al., “Tensile Characterization and Constitutive Modeling of Sintered Nano-Silver Particles Over a Range of Strain Rates and Temperatures,” Microelectronics Reliability, vol. 132, 2022.
[CrossRef] [Google Scholar] [Publisher Link]
[21] Jens Heilmann et al., “Physics of Failure based Lifetime Modelling for Sintered Silver Die Attach in Power Electronics: Accelerated Stress Testing by Isothermal Bending and Thermal Shock in Comparison,” Microelectronics Reliability, vol. 145, 2023.
[CrossRef] [Google Scholar] [Publisher Link]
[22] Rosidah Alias, and Sabrina Mohd Shapee, Rheological Behaviors and Their Correlation with Printing Performance of Silver Paste for LTCC Tape, Rheology, IntechOpen, 2012.
[CrossRef] [Google Scholar] [Publisher Link]
[23] Kun Ma et al., “A Micromechanical Analysis to the Viscoplastic Behavior of Sintered Silver Joints under Shear Loading,” Materials, vol. 16, no. 12, pp. 1-15, 2023.
[CrossRef] [Google Scholar] [Publisher Link]
[24] Wei Liu et al., “Recent Progress in Rapid Sintering of Nanosilver for Electronics Applications,” Micromachines, vol. 9, no. 7, pp. 1-17, 2018.
[CrossRef] [Google Scholar] [Publisher Link]
[25] Yujun Gao et al., “Effects of Organic Vehicle on the Rheological and Screen-Printing Characteristics of Silver Paste for LTCC Thick Film Electrodes,” Materials, vol. 15, no. 5, pp. 1-11, 2022.
[CrossRef] [Google Scholar] [Publisher Link]
[26] Hui Yang, and Jihui Wu, “Improvement of Sintering Performance of Nanosilver Paste by Tin Doping,” Journal of Nanomaterials, vol. 2020, pp. 1-6, 2020.
[CrossRef] [Google Scholar] [Publisher Link]
[27] Najwa Ibrahim, John O. Akindoyo, and M. Mariatti, “Recent Development in Silver-based Ink for Flexible Electronics,” Journal of Science: Advanced Materials and Devices, vol. 7, no. 1, pp. 1-13, 2022.
[CrossRef] [Google Scholar] [Publisher Link]
[28] NanoTach® Die-Attach Products, NBE Technologies LLC. [Online]. Available: https://www.nbetech.com/products