Interfacial intermetallic developments of Sn-3.0Ag-0.5Cu-2.0ZnO lead free solder

2021 23rd European Microelectronics and Packaging Conference &Amp; Exhibition (EMPC)

Krammer

et al. 2021

In the present study, SACX0307-ZnO and SACX0307-TiO2 nano-composite solder pastes were fabricated. The ceramic reinforcements were used in 1wt% and with different primary particle sizes between 50-200nm. The soldering properties and microstructure of the solder joints were investigated. The nano-particles were mixed into the solder paste by standard ball milling process. Reflow soldering technology has been applied to prepare solder joints and spreading tests from the different solder alloys. The solder joints were evaluated by shear test, and cross-sections were prepared to investigate the metallographic properties by Scanning Electron Microscopy (SEM). The different ceramic nano-particles had different effects on the solderability of solder alloys. Best results were observed in the case of TiO2 nano-particles with improved wetting and mechanical strength. The microstructural investigations showed considerable grain refinement and the modified grain boundary/interfacial properties, which could cause the increase of the mechanical parameters.

Section: Introductionmentioning

confidence: 99%

Properties of nano-composite SACX0307-(ZnO, TiO₂) solders

2021 23rd European Microelectronics and Packaging Conference &Amp; Exhibition (EMPC)

Krammer

et al. 2021

“…The ZnO has similar properties with other oxide ceramic nano-particle alloys in solder material. The ZnO micro or nano-particles added to SnAgCu based solder alloys have suppressed the IMC layer growth at the soldersubstrate interface [9][10]. It was shown in solder alloys that ZnO nano-particles decrease the diffusion coefficient, and this suppresses the formation and growth of the IMC layer.…”

Section: Introductionmentioning

confidence: 99%

Tin Whisker Susceptibility of SAC0307-ZnO Composite Solder Joints

Choi

2022 45th International Spring Seminar on Electronics Technology (ISSE)

et al. 2022

In the present study, tin (Sn) whisker growth has been observed from SAC0307-ZnO composite solder joints. The commercial SAC0307 solder alloy was reinforced by ZnO nano-particles, which resulted in composite solder joints. The ZnO nano-particles were mixed into the solder paste in a 0.25 wt% volume fraction, using the ball milling process. Solder joints were prepared from the composite solder alloy and from the reference SAC0307, on Ag surface finish by conventional SMT. The solder joints were exposed to an accelerated lifetime test (85 ºC/85 RH% THB, 3000 hours) to enhance the Sn whisker growth. Corrosion spots were observed after 1000 hours of aging, and the first whiskers appeared after 1500 hours of aging on the reference SAC0307 solder joints. In the case of the ZnO composite solder joints, non of the previous phenomena were observed during 3000 hours of THB aging. Furthermore the mechanical strength of the solder joints was investigated, but it was found that the ZnO nano-particle could not increase the mechanical properties of the composite solder joints considerably.

“…The effect of ZnO addition has a similar effect to some extent. In the case of SnAgCu-based solder alloys, the addition of ZnO micro-and nanoparticles resulted in a thinner IMC layer at the solder-substrate interface [12][13]. The wettability was also increased slightly over 0.5 wt% addition [13].…”

Section: Introductionmentioning

confidence: 99%

Soldering with SACX0307-(TiO₂/ZnO) nano-composite solder alloys

2021 44th International Spring Seminar on Electronics Technology (ISSE)

Krammer

et al. 2021

In the present research, the solderability of SACX0307 nano-composite solder alloys was studied. The SACX0307 solder alloys were reinforced by ZnO or TiO2 nanoparticles. The nanoparticles were mixed into the solder paste in different volume fractions between 0.25 and 1 wt%, using the ball milling process. Wetting and mechanical tests were performed with the nano-composite solder alloys and with the reference SACX0307 as well. It was found that the ceramic reinforcements did not have a considerable effect on the wetting of the composite solder alloys. However, the shear strength of the nano-composite solder joints increased compared to the reference SACX0307. Generally, the application of TiO2 nanoparticles resulted in a bit better solderin properties than the ZnO nanoparticles. No straightforward correlation was found between the volume fraction of the ceramic nanoparticles and the soldering properties of the nano-composite solder alloys. Expect in the case of the ZnO nanoparticles, when the volume fraction should not exceed 0.5wt% since it can inhibit the proper reflow of the solder paste.