This paper reports a novel fabrication strategy for flexible electronics based on the parylene-MEMS (micro-electromechanical system) technique. A set of parylene-filled trenches is used to mechanically connect silicon-based functional units and realize a flexible 4×6 temperature controlling array as a preliminary demonstration. The trench-filling performance of the parylene deposition is carefully studied, and an optimized process is established to minimize the keyhole inside the parylene-filled trench. The effect of trench width on the flexibility and bendability of the prepared flexible electronics devices is analyzed by finite element modeling. Performances of the thermal/electrical isolation and the mechanical connection of the prepared parylene-filled trenches have been tested. The experimental results indicate that the highest thermal isolation efficiency is approximately 72.5% with the 10 paralleled, 7 μm wide and 50 μm deep parylene-filled trenches. The leakage current of the 10 paralleled, 5 μm wide and 100 μm deep parylene-filled trenches is less than 2 pA under a voltage of 100 V. Besides, these parylene-filled trenches acting as the flexible linkage of connected silicon-based functional units exhibit high connection performance without rupture when the loading pressure is under 200 kPa. Due to the powerful silicon microfabrication capability and excellent compatibility of the parylene-MEMS technique, the present flexible electronics strategy holds a promising potential for applications in various areas.
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This work was financially supported by National Natural Science Foundation of China (Grant No. U1613215), Beijing Natural Science Foundation (Grant No. L172005), and National Basic Research Program of China (973) (Grant No. 2015CB352100).
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Dong, X., Zhang, M., Lei, Y. et al. Parylene-MEMS technique-based flexible electronics. Sci. China Inf. Sci. 61, 060419 (2018). https://doi.org/10.1007/s11432-018-9430-2
- flexible electronics
- trench filling
- temperature controlling array