Photothermal Lithography for Realizing a Stretchable Multilayer Electronic Circuit Using a Laser

Sangmin Song; Hyejun Hong; Kyung Yeun Kim; Kyun Kyu Kim; Jaewoo Kim; Daeyeon Won; Soyoung Yun; Joonhwa Choi; Young-In Ryu; Kyungwoo Lee; Jaeho Park; Joohyuk Kang; Junhyuk Bang; Hyunseon Seo; Yu-Chan Kim; Daeho Lee; Haechang Lee; Jinwoo Lee; Suk-Won Hwang; Seung Hwan Ko; Hojeong Jeon; Wonryung Lee

doi:10.1021/acsnano.3c06207

Photothermal Lithography for Realizing a Stretchable Multilayer Electronic Circuit Using a Laser

ACS Nano. 2023 Nov 14;17(21):21443-21454. doi: 10.1021/acsnano.3c06207. Epub 2023 Oct 19.

Authors

Sangmin Song^{1

2}, Hyejun Hong^{1

3}, Kyung Yeun Kim^{1

2}, Kyun Kyu Kim⁴, Jaewoo Kim^{1

5}, Daeyeon Won², Soyoung Yun¹, Joonhwa Choi², Young-In Ryu^{1

3}, Kyungwoo Lee¹, Jaeho Park¹, Joohyuk Kang^{1

3}, Junhyuk Bang^{1

2}, Hyunseon Seo⁶, Yu-Chan Kim¹, Daeho Lee⁷, Haechang Lee¹, Jinwoo Lee⁸, Suk-Won Hwang⁵, Seung Hwan Ko², Hojeong Jeon^{1

5}, Wonryung Lee^{1

9}

Affiliations

¹ Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea.
² Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea.
³ Department of Materials Science and Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea.
⁴ Department of Chemical Engineering, Stanford University, Stanford, California 94305, United States.
⁵ KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Republic of Korea.
⁶ School of Medicine, Sungkyunkwan University, Suwon 16419, Republic of Korea.
⁷ Department of Mechanical Engineering, Gachon University, Seongnam 13120, Republic of Korea.
⁸ Department of Mechanical, Robotics, and Energy Engineering, Dongguk University, Seoul 04620, Republic of Korea.
⁹ Division of Bio-Medical Science & Technology, University of Science & Technology (UST), Seoul 02792, Republic of Korea.

PMID: 37857269
DOI: 10.1021/acsnano.3c06207

Abstract

Photolithography is a well-established fabrication method for realizing multilayer electronic circuits. However, it is challenging to adopt photolithography to fabricate intrinsically stretchable multilayer electronic circuits fully composed of an elastomeric matrix, due to the opacity of thick stretchable nanocomposite conductors. Here, we present photothermal lithography that can pattern elastomeric conductors and via holes using pulsed lasers. The photothermal-patterned stretchable nanocomposite conductor exhibits 3 times higher conductivity (5940 S cm^-1) and 5 orders of magnitude lower resistance change (R/R₀ = 40) under a 30% strained 5000th cyclic stretch, compared to those of a screen-printed conductor, based on the percolation network formed by spatial heating of the laser. In addition, a 50 μm sized stretchable via holes can be patterned on the passivation without material ablation and electrical degradation of the bottom conductor. By repeatedly patterning the conductor and via holes, highly conductive and durable multilayer circuits can be stacked with layer-by-layer material integration. Finally, a stretchable wireless pressure sensor and passive matrix LED array are demonstrated, thus showing the potential for a stretchable multilayer electronic circuit with durability, high density, and multifunctionality.

Keywords: laser fabrication; photothermal lithography; stretchable electronics; stretchable multilayer electronic circuit; stretchable nanocomposites.