Effect of interconnection area on shear strength of sintered joint with nano‐silver paste

A silver precursor (silver 2-ethylhexanoate) and silver nanoparticles were synthesized and used to prepare a low sintering temperature nano-silver paste (PM03). We optimized the amount of silver 2-ethylhexanoate added and the sintering temperature to obtain the best performance of the nano-silver paste. The relationship between the microstructures and properties of the paste was studied. The addition of silver 2-ethylhexanoate resulted in less porosity, leading to lower resistivity and higher shear strength. Thermal compression of the paste PM03 at 250 °C with 10 MPa pressure for 30 min was found to be the proper condition for copper-to-copper bonding. The resistivity was (3.50 ± 0.02) × 10−7 Ω∙m, and the shear strength was 57.48 MPa.

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Mechanical property and reliability of bimodal nano-silver paste with Ag-coated SiC particles

Soldering & Surface Mount Technology ◽

10.1108/ssmt-05-2018-0014 ◽

2019 ◽

Vol 31 (4) ◽

pp. 193-202 ◽

Cited By ~ 4

Author(s):

Qiaoran Zhang ◽

Abdelhafid Zehri ◽

Jiawen Liu ◽

Wei Ke ◽

Shirong Huang ◽

...

Keyword(s):

Mechanical Property ◽

Shear Strength ◽

Sintering Temperature ◽

Temperature Stability ◽

High Temperature Stability ◽

Silver Paste ◽

Content Type ◽

Nano Silver ◽

Sintering Time ◽

Sic Particles

Purpose This study aims to develop a bimodal nano-silver paste with improved mechanical property and reliability. Silicon carbide (SiC) particles coated with Ag were introduced in nano-silver paste to improve bonding strength between SiC and Ag particles and enhance high-temperature stability of bimodal nano-silver paste. The effect of sintering parameters such as sintering temperature, sintering time and the proportion of SiC particles on mechanical property and reliability of sintered bimodal nano-silver structure were investigated. Design/methodology/approach Sandwich structures consist of dummy chips and copper substrates with nickel and silver coating bonded by nano-silver paste were designed for shear testing. Shear strength testing was conducted to study the influence of SiC particles proportions on the mechanical property of sintered nano-silver joints. The reliability of the bimodal nano-silver paste was evaluated experimentally by means of shear test for samples subjected to thermal aging test at 150°C and humidity and temperature testing at 85°C and 85 per cent RH, respectively. Findings Shear strength was enhanced obviously with the increase of sintering temperature and sintering time. The maximum shear strength was achieved for nano-silver paste sintered at 260°C for 10 min. There was a negative correlation between the proportion of SiC particles and shear strength. After thermal aging testing and humidity and temperature testing for 240 h, the shear strength decreased a little. High-temperature stability and high-hydrothermal stability were improved by the addition of SiC particles. Originality/value Submicron-scale SiC particles coated with Ag were used as alternative materials to replace part of nano-silver particles to prepare bimodal nano-silver paste due to its high thermal conductivity and excellent mechanical property.

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Feasibility investigation and characterization of low-pressure-assisted sintered-silver bonded large-area DBA plates

Soldering & Surface Mount Technology ◽

10.1108/ssmt-07-2019-0023 ◽

2019 ◽

Vol 32 (3) ◽

pp. 129-136 ◽

Cited By ~ 1

Author(s):

Yansong Tan ◽

Xin Li ◽

Xu Chen ◽

Zhenwen Yang ◽

Guo-Quan Lu

Keyword(s):

Shear Strength ◽

Double Layer ◽

Low Pressure ◽

Large Area ◽

Silver Paste ◽

Content Type ◽

Nano Silver ◽

Average Shear Strength ◽

Bonding Method ◽

Sintered Silver

Purpose This paper aims to use nano-silver paste to design a new bonding method for super-large-area direct-bonded-aluminum (DBA) plates. It compared several frequently used bonding methods and proved the feasibility of an optimized low-pressure-assisted double-layer-printed silver sintering technology for large-area bonding to increase the thermal conductivity of power electronic modules with high junction temperature, higher power density and higher reliability. Design/methodology/approach The bonding profile was optimized by using transparent glasses as substrates. Thus, the bonding qualities could be directly characterized by optical observation. After sintering, the bonded DBA samples were characterized by nondestructive X-ray computed tomography system, scanning electron microscopy equipped with an energy dispersive spectrometer. Finally, bonding stress evolution was characterized by shear tests. Findings Low-pressure-assisted large-area double-layer-printed bonding process consisting of six-step was successfully developed to bond DBA substrates with the size of 50.8 × 25.4 mm. The thickness of the sintered-silver bond-line was between 33 and 74 µm with the average porosity of 12.5 per cent. The distribution of shear strength along the length of DBA/DBA bonded sample was from 9.7 to 18.8 MPa, with average shear strength of 15.5 MPa. The typical fracture primarily propagated in the sintered-silver layer and partially along the Ni layer. Research limitations/implications The bonding stress needs to be further improved. Meanwhile, the thermal and electrical properties are encouraged to test further. Practical implications If nano-silver paste can be used as thermal interfacial material for super-large-area bonding, the thermal performance will be improved. Social implications The paper accelerated the use of nano-silver paste for super-large-area DBA bonding. Originality/value The proposed bonding method greatly decreased the bonding pressure.

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Mechanical and electrical characteristics of silver stabilizer layer prepared by using nano silver paste for coated conductor

Physica C Superconductivity ◽

10.1016/j.physc.2009.05.250 ◽

2009 ◽

Vol 469 (15-20) ◽

pp. 952-955 ◽

Cited By ~ 6

Author(s):

J.B. Lee ◽

S.U. Lee ◽

S.S. Kim ◽

B.J. Kim ◽

H.J. Kim ◽

...

Keyword(s):

Coated Conductor ◽

Electrical Characteristics ◽

Silver Paste ◽

Nano Silver

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Dynamic Resistance Monitoring of Nano Silver Paste during Sintering and Thermoelectric Aging Process

Journal of Mechanical Engineering ◽

10.3901/jme.2020.08.060 ◽

2020 ◽

Vol 56 (8) ◽

pp. 60

Author(s):

MA Jingxuan ◽

WANG Shang ◽

YANG Dongsheng ◽

TIAN Yanhong

Keyword(s):

Aging Process ◽

Dynamic Resistance ◽

Silver Paste ◽

Nano Silver ◽

Resistance Monitoring

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Development of low temperature sintered nano silver pastes using MO technology and resin reinforcing technology

Additional Conferences (Device Packaging HiTEC HiTEN & CICMT) ◽

10.4071/hitec-wa22 ◽

2014 ◽

Vol 2014 (HITEC) ◽

pp. 000172-000177

Author(s):

Koji Sasaki ◽

Noritsuka Mizumura

Keyword(s):

Shear Strength ◽

Low Temperature ◽

Thermal Cycling ◽

Thick Film ◽

Thermal Performance ◽

Low Temperature Sintering ◽

Thermal Cycling Test ◽

Nano Silver ◽

Cycling Test ◽

Thick Film Technology

Traditional thick film technology is widely used in various electronics products. There are two type of paste based on thick film technology. Typically, over 400°C is required for high temperature sintering type which contains glass for adhesion function. It shows high electrical and thermal performance. On the other hand, 150–300°C range process is used for low temperature process type as silver epoxy. In last decade, nano silver technology shows amazing progress to address low temperature operation by low temperature sintering. This paper will discuss the results on fundamental study of newly developed nano silver pastes with unique approach which uses MO (Metallo-organic) technology and resin reinforcing technology. Nano silver pastes contain several types of dispersant as surface coating to prevent agglomeration of the particles. Various coating technique has been reported to optimize sintering performance and stability. MO technology provides low temperature sintering capability by minimizing the coating material. The nano silver pastes show high electrical and thermal performance. However, degradation of die shear strength has been found by thermal cycling test due to the fragility of porous sintered structure. To improve the mechanical property, resin reinforcing technology has been developed. By adding special resin to the pastes, the porous area is filled with the resin and the sintered structure is reinforced. Degradation of die shear strength was not found by thermal cycling test to 1000 cycles. Nano silver pastes using MO technology and resin reinforcing technology will meet lots of requirement on various thick film applications.

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