Technical ABSTRACTS

In Case You Missed It

Flexible Electronics

“Layer-By-Layer Printing Strategy for High-Performance Flexible Electronic Devices with Low-Temperature Catalyzed Solution-Processed SiO2”
Authors: Qingqing Sun, et al.

Abstract: Additive printing techniques have been widely investigated for fabricating multilayered electronic devices. In this work, a layer-by-layer printing strategy is developed to fabricate multilayered electronics, including 3-D conductive circuits and thin-film transistors (TFTs) with low-temperature catalyzed, solution-processed SiO2 (LCSS) as the dielectric. Ultrafine, ultrasmooth LCSS films can be facilely formed at 90°C on a wide variety of organic and inorganic substrates, offering a versatile platform to construct complex heterojunction structures with layer-by-layer fashion at microscale. The high-resolution 3-D conductive circuits formed with gold nanoparticles inside the LCSS dielectric demonstrate a high-speed response to the transient voltage in less than 1µs. The TFTs with semiconducting single-wall carbon nanotubes can be operated with the accumulation mode at a low voltage of 1V and exhibit average field-effect mobility of 70cm2 V−1 s−1, on/off ratio of 107, small average hysteresis of 0.1V, and high yield (up to 100%), as well as long-term stability, high negative-gate bias stability, and good mechanical stability. Therefore, the layer-by-layer printing strategy with the LCSS film is promising to assemble large-scale, high-resolution, and high-performance flexible electronics and to provide a fundamental understanding for correlating dielectric properties with device performance. (Small Methods, May 21, 2021; https://onlinelibrary.wiley.com/doi/10.1002/smtd.202100263)

Solder

“Mechanical, Photoelectric and Thermal Reliability of SAC 307 Solder Joints with Ni-decorated MWCNTs for Flip-Chip LED Package Component During Aging”
Authors: Xinmeng Zhai, et al.

Abstract: This study aims to study the mechanical, photoelectric and thermal reliability of SAC 307 solder joints with Ni-decorated MWCNTs for flip-chip light-emitting diode (LED) package component during aging. By adding nanoparticles (Ni-multi-walled carbon nanotubes [MWCNTs]) to the solder paste, the shear strength and fatigue resistance of the brazed joint can be improved. However, the aging properties of Ni-modified MWCNTs composite solder joints have not been deeply studied. In this research, the mechanical, photoelectric and thermal reliability of SAC 307 packaged flip-chip LEDs with Ni-MWCNTs added during aging were studied. (Soldering & Surface Mount Technology, Sept. 23, 2022; https://www.emerald.com/insight/content/doi/10.1108/SSMT-08-2021-0059/full/html)

Sustainability

“Biobased Materials for Sustainable Printed Circuit Boards”
Authors: Oladele A. Ogunseitan, et al.

Abstract: Electronic waste, with printed circuit boards (PCBs) at its heart, is the fastest-growing category of hazardous solid waste in the world. New materials, in particular biobased materials, show great promise in solving some of the sustainability and toxicity problems associated with PCBs, although several challenges still prevent their practical application. (Nature Reviews Materials, September 2022; https://www.nature.com/articles/s41578-022-00485-2)

Wearable Electronics

“A Flexible Electronic Strain Sensor for the Real-Time Monitoring of Tumor Regression”
Authors: Alex Abramson, et al.

Abstract: The authors present a commercially scalable wearable electronic strain sensor that automates the in vivo testing of cancer therapeutics by continuously monitoring the micrometer-scale progression or regression of subcutaneously implanted tumors at the minute time scale. In two in vivo cancer mouse models, the sensor discerned differences in tumor volume dynamics between drug- and vehicle-treated tumors within 5 hr. following therapy initiation. These short-term regression measurements were validated through histology, and caliper and bioluminescence measurements taken over weeklong treatment periods demonstrated the correlation with longer-term treatment response. (Science Advances, Sept. 16, 2022, https://www.science.org/doi/10.1126/sciadv.abn6550)

This column provides abstracts from recent industry conferences, technical journals and company white papers. Our goal is to provide an added opportunity for readers to keep abreast of technology and business trends.