Strategies for body-conformable electronics

• Published in: Matter Vol. 5; no. 4; pp. 1104 - 1136
• Main Authors: Liu, Siyi, Rao, Yifan, Jang, Hongwoo, Tan, Philip, Lu, Nanshu
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 06.04.2022
• Subjects: adhesion; bio-integration; conformable electronics; flexible electronics; stretchable electronics; flexible electronics; bio-integration; adhesion; conformable electronics; stretchable electronics
• ISSN: 2590-2385; 2590-2385
• DOI: 10.1016/j.matt.2022.02.006

Advances in flexible and stretchable electronics have enabled an unprecedented level of coupling between electronics and bio-tissues by overcoming obstacles associated with the bio-tissues’ curvilinearity, softness, deformability, and wetness. This review begins by detailing the outstanding challenges in achieving body-conformable electronics stemming from the disparate properties of bio-tissues and man-made materials and the complexity of their interfaces. Given tissue properties, an existing mechanics model has revealed how device softness and interfacial adhesion govern the bio-electronics conformability. Therefore, we first summarize methods for improving the mechanical compliance of electronics through both material engineering and structural design. Then, we discuss strategies to enhance bio-electronics adhesion in both dry and wet environments. We point out that innovative bio-electronics integration procedures also have a significant impact on bio-electronics conformability. We conclude by providing an outlook into future opportunities and proposing a holistic approach to strategizing body-conformable electronics. [Display omitted] Unobstructive, long-term, and high-fidelity human body sensing and stimulation must overcome the challenges of manifold mismatches between bio-tissues and man-made materials. The emergence of body-conformable electronics is a promising solution to these inherent obstacles. In the last two decades, various strategies have been developed to promote bio-electronics conformability by (1) improving device thinness and compliance, (2) enhancing bio-electronics interfacial adhesion, and (3) refining the bio-integration process. A successful body-conformable electronic device can only be created through comprehensive consideration of all three aspects. This review summarizes recent advancements in these three directions and proposes a holistic strategy. We envision that future research efforts in body-conformable electronics will focus on new functionalities, enhanced performance, and personalization. The rapid progress in body-conformable electronics shall meet the ever-growing demands in telemedicine, mobile health, points of care, and human-machine interfaces. Body-conformable electronics allow for unobstructive, long-term, and high-fidelity human body sensing and stimulation. In this review, challenges and governing parameters of body-conformable electronics are first discussed. Thereafter, strategies to achieve body conformability are summarized from three aspects: improving the mechanical compliance of electronics, enhancing bio-electronics adhesion, and inventing new bio-integration procedures. In the end, we provide an outlook into future opportunities and suggest a holistic view of body-conformable electronics.