The conventional fabrication method for stretchable electronics is labor and cost intensive, which significantly hinders their translation from lab prototypes to clinical use. To overcome such limitations, my group developed a dry and freeform (subtractive) manufacturing process for the rapid prototyping of stretchable e-tattoos called the “cut-and-paste” method in 2015.14 In 2019, we upgraded it to the “cut-solder-paste” process (f) which allows the incorporation of rigid integrated circuits (ICs) such as microprocessors and near field communication (NFC) chips to form wireless e-tattoos (e.g. k).15 We reported that multi-channel, large-area but ultrathin, filamentary e-tattoos could be reliably pasted onto non-developable human body through a math concept called the Cartan development (g).16 Such e-tattoo conformed to the forearm as shown in (m) could conduct 16-channel surface electromyography (sEMG), which can be used for sign language recognition and prosthesis control.
14 Yang, S., Chen, Y.C., Nicolini, L., Pasupathy, P., Sacks, J., Becky, S., Yang, R., Daniel, S., Chang, Y.F., Wang, P., Schnyer, D., Neikirk, D., and Lu, N.: ‘”Cut-and-Paste” Manufacture of Multiparametric Epidermal Sensor Systems’, Adv Mater, 2015, 27, (41), pp. 6423–6430
15 Jeong, H., Wang, L., Ha, T., Mitbander, R., Yang, X., Dai, Z., Qiao, S., Shen, L., Sun, N., and Lu, N.: ‘Modular and Reconfigurable NFC-Enabled Wireless Electronic Tattoos for Biometric Sensing’, Advanced Materials Technologies, 2019, pp. 1900117
16 Wang, Y., Yin, L., Bai, Y., Liu, S., Zhou, Y., Wang, L., Hou, C., Yang, Z., Wu, H., Ma, J., Shen, Y., Deng, P., Zhang, S., Duan, T., Li, Z., Ren, J., Xiao, L., Yin, Z., Lu, N., and Huang, H.: ‘Electrically compensated, tattoo-like electrodes for epidermal electrophysiology at scale’, Sci Adv, 2020, 6, pp. eabd0996