Abstract
Integrating deformable interconnects with inorganic functional materials establishes a path to high-performance stretchable electronics. A number of applications demand that these systems sustain large deformations under repetitive loading. In this manuscript, the influence of the elastomeric substrate on the stretchability of serpentine interconnects is investigated theoretically and experimentally. Finite element analyses (FEA) reveal a substantial increase in the elastic stretchability with reductions in substrate thickness. Low-cycle fatigue tests confirm this trend by examining the stretch required to form fatigue cracks associated with plastic deformation. To elucidate the mechanics governing this phenomenon, the buckling behaviors of deformed serpentine interconnects on substrates of various thicknesses are examined. The analytical model and FEA simulations suggest a change in the buckling mode from local wrinkling to global buckling below a critical thickness of the substrate. Scanning electron microscope and 3D optical profiler studies verify this transition in buckling behavior. The global buckling found in thin substrates accommodates large stretching prior to plastic deformation of the serpentines, thereby drastically enhancing the stretchability of these systems.
Original language | English (US) |
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Article number | 1702589 |
Journal | Advanced Functional Materials |
Volume | 27 |
Issue number | 37 |
DOIs | |
State | Published - Oct 5 2017 |
Funding
T.P., M.P., and Y.M. contributed equally to this work. T.P. and X.F. acknowledge the support from the National Basic Research Program of China (Grant No. 2015CB351900). T.P. acknowledges the support from Fundamental Research Funds for the Central Universities of China (Grant No. ZYGX2016KYQD132). Y.M. and X.F. acknowledge the support from the National Natural Science Foundation of China (Grant Nos. 11402135 and 11320101001). Y.H. acknowledges the support from the NSF (Grant Nos. DMR-1121262, CMMI-1400169, and CMMI-1534120) and the NIH (Grant No. R01EB019337).
Keywords
- buckling
- flexible electronics
- plasticity
- serpentine interconnects
- stretchable electronics
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- General Chemistry
- Biomaterials
- General Materials Science
- Condensed Matter Physics
- Electrochemistry