Nanofabrication of flexible thin-film bioelectronics for long-term stable neural signal recording

Abstract

Establishing a long-term stable and effective interface for brain is a significant milestone for all neural implants. Recent studies have demonstrated that tissue-level soft and flexible materials and devices can provide such stability for neural implants. Therefore, engineering suitable materials and developing fabrication methods for soft and flexible thin-film electric probes to further exploit their potential are essential to advancing the field. This thesis demonstrates the comprehensive methods required for developing electrical recording devices and for analyzing the acquired neural data. It presents the design, fabrication, and in vivo implantation of flexible thin-film electronic devices. The materials and fabrication processes are engineered to create structures that can more closely mimic the mechanical properties of brain tissue, in contrast to traditional stiff neural probes. The device designs in this work feature serpentine-shaped ribbons for stretchability and tetrode-like electrode configuration to enable the measurement of single-unit neural activities.