RESUMO
Tactile function is essential for human life as it enables us to recognize texture and respond to external stimuli, including potential threats with sharp objects that may result in punctures or lacerations. Severe skin damage caused by severe burns, skin cancer, chemical accidents, and industrial accidents damage the structure of the skin tissue as well as the nerve system, resulting in permanent tactile sensory dysfunction, which significantly impacts an individual's daily life. Here, we introduce a fully-implantable wireless powered tactile sensory system embedded artificial skin (WTSA), with stable operation, to restore permanently damaged tactile function and promote wound healing for regenerating severely damaged skin. The fabricated WTSA facilitates (i) replacement of severely damaged tactile sensory with broad biocompatibility, (ii) promoting of skin wound healing and regeneration through collagen and fibrin-based artificial skin (CFAS), and (iii) minimization of foreign body reaction via hydrogel coating on neural interface electrodes. Furthermore, the WTSA shows a stable operation as a sensory system as evidenced by the quantitative analysis of leg movement angle and electromyogram (EMG) signals in response to varying intensities of applied pressures.
Assuntos
Pele Artificial , Humanos , Biônica , Tato/fisiologia , Pele , Cicatrização , Órgãos dos SentidosRESUMO
To achieve both the synergistic advantages of outstanding flexibility in organic dielectrics and remarkable dielectric/insulating properties in inorganic dielectrics, a plasma-polymerized hafnium oxide (HfOx) hybrid (PPH-hybrid) dielectric is proposed. Using a radio-frequency magnetron cosputtering process, the high-k HfOx dielectric is plasma-polymerized with polytetrafluoroethylene (PTFE), which is a flexible, thermally stable, and hydrophobic fluoropolymer dielectric. The PPH-hybrid dielectric with a high dielectric constant of 14.17 exhibits excellent flexibility, maintaining a leakage current density of â¼10-8 A/cm2 even after repetitive bending stress (up to 10000 bending cycles with a radius of 2 mm), whereas the HfOx dielectric degrades to be leaky. To evaluate its practical applicability to flexible thin-film transistors (TFTs), the PPH-hybrid dielectric is applied to amorphous indium-gallium-zinc oxide (IGZO) TFTs as a gate dielectric. Consequently, the PPH-hybrid dielectric-based IGZO TFTs exhibit stable electrical performance under the same harsh bending cycles: a field-effect mobility of 16.99 cm2/(V s), an on/off current ratio of 1.15 × 108, a subthreshold swing of 0.35 V/dec, and a threshold voltage of 0.96 V (averaged in nine devices). Moreover, the PPH-hybrid dielectric-based IGZO TFTs exhibit a reduced I-V hysteresis and an enhanced positive bias stress stability, with the threshold voltage shift decreasing from 4.99 to 1.74 V, due to fluorine incorporation. These results demonstrate that PTFE improves both the mechanical durability and electrical stability, indicating that the PPH-hybrid dielectric is a promising candidate for high-performance and low-power flexible electronics.