在電化學生物感測器當中，通常用可植入式電極探針偵測生物體內的神經傳導物質，其中電極材料的選擇相當多元，像是白金(Pt)電極、金電極(Au)、網印碳電極(C)等。通常可根據所將偵測待測分析物的種類，以選定可提供最佳感測靈敏度的電極材料，由於白金穩定性極佳，在測試時電位穩定不易受干擾，且白金電極與生物感測中常用之生物辨識元件-氧化酵素之產物過氧化氫(H2O2)反應所產生的氧化電流很大，因此我們在製備電極時所選擇的材質是白金。此外，由於在進行神經傳導物質濃度偵測時，需將感測器植入生物體內，所以電極探針需具備強韌的機械強度，但是同時應避免破壞生物組織，因此，對於探針尺寸方面要求極高，因此我們採用微機械加工的半導體製程技術去製備探針，整個製程包括微影製程(lithography process)、蝕刻(etching process)、化學氣相沉積(chemical vapor deposition)及物理氣相沉積(physical vapor deposition)，使我們可以得到尺寸規格統一且導電性極佳的微型化電極。在製程方面我們著重由電極探針製程效率，且以大量生產為目標，因此我們在進行電極的微機械加工製程時都，都會選擇最合適的實驗機臺進行製程，並針對製程實驗參數進行最佳化。

Implantable electric chemical biosensors are usually used for the monitoring of neurotransmitters in vivo. There are various electrode materials for the fabrication of biosensors, such as platinum, gold, carbon and so on; here, platinum electrode was chosen as our electrode material since. Platinum has excellent stability for chemical reaction and creates high oxidation current for hydrogen peroxide (the product of most oxidase enzymatic reactions) after the oxidation reaction at the electrode surface. Since when measuring the biosensor in vivo, the biosensor requires to be implanted in the live rodents, it needs good mechanical strength. However, the damage of tissue during the implantation process should be minimized. Therefore, we apply micromachining technology to design miniaturized probes. The micromachining process, includes lithography process, etching process, and chemical and physical evaporation deposition, etc. So that we can get uniform microelectrodes and the resulting electrodes have good conductivity. The purpose of the micromachining process is for mass production, so we optimized the parameters for fabrication and chose the most suitable instruments for the micromachining process of our microelectrode array probes.

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