IEEE Trans Biomed Eng. 2024 Jan;71(1):3-13. doi: 10.1109/TBME.2023.3276477. Epub 2023 Dec 22.
In this paper, the fabrication of perfluoro-alkoxy alkane (PFA) film-based planar neural electrodes was proposed.
The fabrication of PFA-based electrodes started with cleaning of PFA film. The argon plasma pretreatment was performed on the PFA film surface and attached to a dummy silicon wafer. Metal layers were deposited and patterned using the standard Micro Electro Mechanical Systems (MEMS) process. Electrode-sites and pads were opened using reactive ion etching (RIE). Lastly, the electrode patterned PFA substrate film was thermally laminated with the other bare PFA film. Electrical-physical evaluation tests were conducted along with in vitro tests, ex vivo tests and soak tests to evaluate the electrode performance and biocompatibility.
The electrical and physical performance of PFA-based electrodes had better performances compared to other biocompatible polymer-based electrodes. Also, the biocompatibility and longevity were verified by cytotoxicity test, elution test, and accelerated life test.
The PFA film-based planar neural electrode fabrication was established and evaluated. The PFA based electrodes showed excellent benefits such as long-term reliability, low water absorption rate, and flexibility using the neural electrode.
For implantable neural electrodes, hermetic sealing is required for in vivo durability. PFA fulfilled a low water absorption rate with relatively low Young's modulus to increase the longevity and biocompatibility of the devices.
本文提出了一种基于全氟烷氧基烷烃（PFA）薄膜的平面神经电极的制造方法。
基于 PFA 的电极制造从 PFA 薄膜的清洁开始。对 PFA 薄膜表面进行氩等离子体预处理，并将其附着在dummy 硅晶片上。使用标准的微机电系统（MEMS）工艺沉积和图案化金属层。使用反应离子刻蚀（RIE）打开电极位和焊盘。最后，将具有图案的 PFA 基底薄膜与其他裸露的 PFA 薄膜进行热压层合。进行了电气物理评估测试以及体外测试、离体测试和浸泡测试，以评估电极性能和生物相容性。
与其他生物相容的聚合物基电极相比，基于 PFA 的电极具有更好的电气和物理性能。此外，通过细胞毒性试验、洗脱试验和加速寿命试验验证了生物相容性和耐久性。
建立并评估了基于 PFA 薄膜的平面神经电极制造方法。基于 PFA 的电极显示出优异的性能，例如使用神经电极的长期可靠性、低吸水率和柔韧性。
对于可植入的神经电极，体内耐久性需要进行密封。PFA 具有低吸水率和相对较低的杨氏模量，可提高器件的寿命和生物相容性。
