Optimal design of a DC micro-plasma electrode

• Main Authors: Chun-Yao Chang, 張淳堯
• Other Authors: Gou-Jen Wang
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/77689553717416274024

碩士 === 國立中興大學 === 機械工程學系所 === 103 === Recent progress in atmospheric plasma has lead to a widespread application of plasma technology in medicine, such as surface modification of biomaterials and sterilization of medical instruments and materials. Recently, applications have been further spread to the direct treatment of cell using plasma. Plasma can cause electrical, chemical, optical, and thermal effects on biological tissue and can be used for hemostasis, cell proliferation, and tissue reconstruction. If the interactions between plasma and cells can be well investigated by a practical device, it will be contribute to the development of therapeutically applicable plasma. Plasma-on-Chip (POC) devices have been developed to achieve plasma treatment of individual cell. However, the micro cathode of a POC can be easily damaged during the plasma firing. In this study, an optimal DC micro-plasma electrode was designed to enhance the lifetime of the plasma electrode while the micro plasma characteristic can still be achieved. The electrode that composed of a 20 nm titanium layer and a 200 nm gold layer on a silicon substrate was fabricated through photolithography and evaporation. Experimental results illustrated that a micro electrode with a blunt-ended cathode and a flat anode could enhance the firing life-time as many as 30 folds of a double tip electrode. We also fabricated a pure titanium electrode (220 nm in thick) for further prolonging the lifetime of the electrode. Experimental results showed that the pure titanium electrode could further increase the life-time for 60 folds when compared with an Au/Ti hybrid electrode. However, the voltage requirement for the pure titanium electrode is higher than the Au/Ti electrode only by 20 V. The pure titanium microelectrode proposed in this study processes advantages such as low cost, simple fabrication process, and high biocompatibility. Hence, it is highly feasible for POC applications.