On the longevity and inherent hermeticity of silicon-ICs: evaluation of bare-die and PDMS-coated ICs after accelerated aging and implantation studies

Nanbakhsh Kambiz

Shah Idil Ahmad

Lamont Callum

Dücső Csaba

Akgun Ömer Can

Horváth Domonkos

Tóth Kinga

Meszéna Domokos

Ulbert István

Mazza Federico

Constandinou Timothy G.

Serdijn Wouter

Vanhoestenberghe Anne

Donaldson Nick

Giagka Vasiliki

2025

01.03.08. Csillagászat

01.04. Kémiai tudományok

01.06.03.03. Biokémia

01.06.07. Genetika és örökléstan

Silicon integrated circuits (ICs) are central to the next-generation miniature active neural implants, whether packaged in soft polymers for flexible bioelectronics or implanted as bare die for neural probes. These emerging applications bring the IC closer to the corrosive body environment, raising reliability concerns, particularly for chronic use. Here, we evaluate the inherent hermeticity of bare die ICs, and examine the potential of polydimethylsiloxane (PDMS), a moisture-permeable elastomer, as a standalone encapsulation material. For this aim, the electrical and material performance of ICs sourced from two foundries was evaluated through one-year accelerated in vitro and in vivo studies. ICs featured custom-designed test structures and were partially PDMS coated, creating two regions on each chip, uncoated “bare die” and “PDMS-coated”. During the accelerated in vitro study, ICs were electrically biased and periodically monitored. Results revealed stable electrical performance, indicating the unaffected operation of ICs even when directly exposed to physiological fluids. Despite this, material analysis revealed IC degradation in the bare regions. PDMS-coated regions, however, revealed limited degradation, making PDMS a suitable IC encapsulant for years-long implantation. Based on the new insights, guidelines are proposed that may enhance the longevity of implantable ICs, broadening their applications in the biomedical field.

angol

angol

Folyóiratcikk

PeerReviewed

text

https://publikacio.ppke.hu/id/eprint/1953/1/s41467-024-55298-4.pdf

Nanbakhsh Kambiz; Shah Idil Ahmad; Lamont Callum; Dücső Csaba; Akgun Ömer Can; Horváth Domonkos; Tóth Kinga; Meszéna Domokos; Ulbert István; Mazza Federico; Constandinou Timothy G.; Serdijn Wouter; Vanhoestenberghe Anne; Donaldson Nick; Giagka Vasiliki: On the longevity and inherent hermeticity of silicon-ICs: evaluation of bare-die and PDMS-coated ICs after accelerated aging and implantation studies. NATURE COMMUNICATIONS, 16 (1). ISSN 2041-1723 (2025)

MTMT:35664636 10.1038/s41467-024-55298-4

https://publikacio.ppke.hu/id/eprint/1953/

https://doi.org/10.1038/s41467-024-55298-4

MTMT:35664636 10.1038/s41467-024-55298-4