TY - JOUR
T1 - The Effect of Torsional Bending on Reliability and Lifetime of Printed Silver Conductors
AU - Hannila, Esa
AU - Remes, Kari
AU - Kurkela, Timo
AU - Happonen, Tuomas
AU - Keranen, Kimmo
AU - Fabritius, Tapio
N1 - Funding Information:
This work was supported in part by the Business Finland under Project Dnro 3944/31/2014, in part by the Academy of Finland's FIRI funding under Grant 320017, and in part by the European Regional Development Fund's Novel Digitally Fabricated Materials for Electronics, Optics and Medical Applications under Grant A74080
PY - 2020/6
Y1 - 2020/6
N2 - Capability of high-speed and low-cost manufacturing makes the printing techniques a very promising approach for large-area flexible electronics mass manufacturing. Due to fast and intensive technology development, the lack of knowledge about the reliability and lifetime of printed electronics is obvious, requiring further investigation. Especially, the effect of torsional bending on lifetime is a mostly unexplored field of reliability testing. In this article, a torsional bending test of parallel printed silver conductors (0.3-, 0.5-mm pitch) on polymer substrate (polyethylene terephthalate, 125- \mu \text{m} thickness) was conducted and analyzed. According to the experimental results, torsional bending causes wear-out type failures in conductors and the length-to-width (LTW) ratio of the sample's substrate was observed to have a significant impact on reliability. If the LTW ratio is smaller than 3, the lifetime of printed conductor seems to collapse and samples lasted for approximately only 17 bending cycles on average. Lifetime was improved by increasing the LTW ratio and samples withstood over hundreds of cycles with LTW ratio of higher than 15. However, the distance of a conductor from the edge of the substrate was not observed to have any significant influence on the reliability under torsional bending.
AB - Capability of high-speed and low-cost manufacturing makes the printing techniques a very promising approach for large-area flexible electronics mass manufacturing. Due to fast and intensive technology development, the lack of knowledge about the reliability and lifetime of printed electronics is obvious, requiring further investigation. Especially, the effect of torsional bending on lifetime is a mostly unexplored field of reliability testing. In this article, a torsional bending test of parallel printed silver conductors (0.3-, 0.5-mm pitch) on polymer substrate (polyethylene terephthalate, 125- \mu \text{m} thickness) was conducted and analyzed. According to the experimental results, torsional bending causes wear-out type failures in conductors and the length-to-width (LTW) ratio of the sample's substrate was observed to have a significant impact on reliability. If the LTW ratio is smaller than 3, the lifetime of printed conductor seems to collapse and samples lasted for approximately only 17 bending cycles on average. Lifetime was improved by increasing the LTW ratio and samples withstood over hundreds of cycles with LTW ratio of higher than 15. However, the distance of a conductor from the edge of the substrate was not observed to have any significant influence on the reliability under torsional bending.
KW - Accelerated lifetime
KW - Flexible electronics
KW - Large-area electronics
KW - Printed electronics
KW - Reliability testing
UR - http://www.scopus.com/inward/record.url?scp=85085584516&partnerID=8YFLogxK
U2 - 10.1109/TED.2020.2990125
DO - 10.1109/TED.2020.2990125
M3 - Article
AN - SCOPUS:85085584516
VL - 67
SP - 2522
EP - 2528
JO - IEEE Transactions on Electron Devices
JF - IEEE Transactions on Electron Devices
SN - 0018-9383
IS - 6
M1 - 9089357
ER -