High-Density Flexible Electrode Arrays for Next-Generation Brain-Computer Interfaces

Rachel Kim; Marcus Lindqvist; Hao Zheng

doi:10.55001/gast.v1i2.66

Abstract

Brain-computer interfaces (BCIs) require electrode arrays that simultaneously achieve high spatial resolution, mechanical compliance, and long-term biocompatibility. We fabricate ultra-flexible, high-density microelectrode arrays (HD-MEAs) with 1,024 channels on a 4 μm-thick parylene-C substrate using photolithography and lift-off metallization. The arrays conform to cortical surface curvature with <5% impedance increase after 10,000 bending cycles at 5 mm radius. In vivo recordings from macaque motor cortex demonstrate single-unit resolution across 256 simultaneously active channels, with signal-to-noise ratio (SNR) of 4.8 ± 0.6. A wireless headstage transmits neural data at 30 Mbps with 24-hour battery life, enabling untethered BCI operation for motor prosthesis control applications.

Author Biographies

Rachel Kim Department of Bioengineering, Stanford University, Stanford, CA 94305, USA

Rachel Kim is an associate professor at Department of Bioengineering, Stanford University, Stanford, CA 94305, USA. Their research focuses on energy systems, with over 75 publications in peer-reviewed journals.
Marcus Lindqvist Neuroscience Institute, Karolinska Institutet, 171 77 Stockholm, Sweden

Marcus Lindqvist is a research fellow at Neuroscience Institute, Karolinska Institutet, 171 77 Stockholm, Sweden. Their research focuses on environmental engineering, with over 32 publications in peer-reviewed journals.
Hao Zheng School of Microelectronics, Fudan University, Shanghai 200433, China

Hao Zheng is a research fellow at School of Microelectronics, Fudan University, Shanghai 200433, China. Their research focuses on biomedical engineering, with over 26 publications in peer-reviewed journals.