Abstract
In order to implement a nanowire-integrated device, well-aligned arrays of a silicon nanowires are necessary for scalable and repeatable mass production. Especially for biomedical applications in neural engineering, device flexibility robust to mechanical bending, without compromising the electrical performance, is a key issue to be resolved. In this paper, a simple fabrication method and the large-scale integration of silicon-nanowire arrays is proposed by combining top–down fabrication with nanowire transfer on flexible substrate for applications in high-resolution neural stimulation microelectrodes. The arrayed silicon nanowires are fabricated on a p-type, (111)-oriented, single-crystalline-silicon substrate by a top-down process that includes silicon dry etching, silicon wet etching, and wet oxidation. After the fabrication of nanowire arrays, the device is transferred to flexible substrate using polyimide coating, electrode formation, and substrate removal. In order to verify the feasibility of the proposed method, a silicon-nanowire field-effect transistor (FET) switch is implemented and evaluated. The results of the proposed method show an excellent potential for high-resolution neural stimulation microelectrodes.
Similar content being viewed by others
References
An S, Lee J, Kim Y, Kim T, Jin D, Min H, Chung H, Kim S (2010). 47.2: 2.8-inch WQVGA flexible AMOLED using high performance low temperature polysilicon TFT on plastic substrates. In: SID symposium digest of technical papers, vol. 41, no. 1, pp. 706–709. Blackwell Publishing Ltd
Chang P, Fan Z, Wang D, Tseng W, Chiou W, Hong J, Lu J (2004) ZnO nanowires synthesized by vapor trapping CVD method. Chem Mater 16(24):5133–5137
Choi DK (2016) Mechanical characterization of biological tissues: Experimental methods based on mathematical modeling. Biomed Eng Lett 6(3):181–195
Fu Y, Cai X, Wu H, Lv Z, Hou S, Peng M, Yu X, Zou D (2012) Fiber supercapacitors utilizing pen ink for flexible/wearable energy storage. Adv Mater 24(42):5713–5718
Garnett E, Yang P (2008) Silicon nanowire radial p–n junction solar cells. J Am Chem Soc 130(29):9224–9225
Gwon TM, Kim C, Shin S, Park JH, Kim SJ (2016) Liquid crystal polymer (LCP)-based neural prosthetic devices. Biomed Eng Lett 6(3):148–163
Im C, Seo JM (2016) A review of electrodes for the electrical brain signal recording. Biomed Eng Lett 6(3):104–112
Kirkham M, Wang X, Wang Z, Snyder R (2007) Solid Au nanoparticles as a catalyst for growing aligned ZnO nanowires: a new understanding of the vapour–liquid–solid process. Nanotechnology 18(36):365304
Lee S, Jung S, Park S, Ahn J, Hong S, Yoo H, Lee M, Cho D (2012) Fabrication and evaluation of silicon nanowire photodetectors on flexible substrate for retinal prosthetic system. Sens Mater 24(4):205–220
Lee S, Jung S, Ahn J, Yoo H, Oh S, Cho D (2014) Microelectrode array with integrated nanowire FET switches for high-resolution retinal prosthetic systems. J Micromech Microeng 24(7):075018
Lee W, Shim S, Park JH, Kim SJ (2016) A three-dimensional neural cell construct for implantable neural interface. Biomed Eng Lett 6(3):172–180
Shahrjerdi D, Bedell S (2012) Extremely flexible nanoscale ultrathin body silicon integrated circuits on plastic. Nano Lett 13(1):315–320
Shan S, Hines A, Zhou D, Greenberg RJ, Humayun MS, Weiland JD (2007) Electrical properties of retinal-electrode interface. J Neural Eng 4(1):S24
Söderström T, Haug F, Terrazzoni-Daudrix V, Ballif C (2008) Optimization of amorphous silicon thin film solar cells for flexible photovoltaics. J Appl Phys 103(11):114509
Viventi J, Kim D, Vigeland L, Frechette E, Blanco J, Kim Y, Avrin A, Tiruvadi V, Hwang S, Vanleer A, Wulsin D, Davis K, Gelber C, Palmer L, Spiegel J, Wu J, Xiao J, Huang Y, Contreras D, Rodgers J, Litt B (2001) Flexible, foldable, actively multiplexed, high-density electrode array for mapping brain activity in vivo. Nat Neurosci 14:1599–1605
Acknowledgements
This work was supported by the Center for Integrated Smart Sensors funded by the Ministry of Science, ICT & Future Planning as Global Frontier Project” (CISS- 2011-0031863).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Lee, S. Top-down fabrication of silicon-nanowire arrays for large-scale integration on a flexible substrate for achieving high-resolution neural microelectrodes. Microsyst Technol 23, 491–498 (2017). https://doi.org/10.1007/s00542-017-3271-6
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00542-017-3271-6