近年來，神經科學(Neuroscience)逐漸成為科學界眾人矚目的焦點並成為這個世紀極有潛力的一門學科。神經學的發展中一個很重要的主題為對於神經信號的判讀與處理，這對於設計諸如人工眼、機械手臂等仿生義肢(Prosthetics)的技術是很重要的基礎。在記載神經信號的技術上，一個尚待突破的瓶頸為細胞膜外量測(Extracellular Recording)的精密度。由於種種的關係，膜外量測的精準度始終無法與傳統膜內量測(Intracellular Recording)並駕齊驅，而這也成為爾等投身神經工程的人員們，努力的目標。

多重電極陣列(Multi-Electrodes Array)主要被應用於膜外 感測一群神經元(neuron)的電生理活動，它的優點在於使用非侵入式(noninvasive)的方法，可對細胞做長時間觀測，並可同時記錄大批樣本。在此篇論文中，我們企圖設計一種可整合刺激(stimulation)與紀錄(recording)的傳感器(transducer)。因為相容於標準CMOS製程(CMOS compatible)，後端感測電路可置於結構底下，可以避免多餘的雜訊干擾；並利用微加工(micromachining)的技術，製造出一個穴型的結構，嘗試在細胞與傳感器之間，形成密封度更加的介面。系統中感測器的結構採用多指金氧半場效電晶體(multi-fingered MOSFET)為基礎，具備可調整的轉導值(transconductance)，並可設計成二維的陣列(2-D array)。論文中將會討論比較過去的文獻，詳述設計的原理和流程，並展示模擬、製程與量測的結果

Recently, neuroscience is becoming a potential subject and held a lots attraction. The development of neuroscience not only promotes the progress of the medicine and pharmacology, but, the most important, the understanding of human being. The techniques of neural recording can be divided into two parts: intracellular recording and extracellular recording. For the noninvasive extracellular recording, long term measurement is available but the precision is still inferior to intracellular recording.

Multi-Electrode array (MEA) is usually involved in a modern extracellular recording system as a fundamental tool. It has the ability to record large amount of samples and the synchronized activities. In this thesis, we develop a CMOS compatible transducer design with the ability of integrating stimulation and recording. The 2D sensor arrays are based on OSFET, which is a MOSFET without polygate, leading direct contact between gate oxide and electrolyte. Taking the advantage of micromachining technique, a hole structure is built above the sensor for a more intimate interface. The back-end readout circuit, with a tunable gain, is just implemented under the structure for avoiding additional disturbance from bonding.

The chip is fabricated in a standard CMOS process with several post-CMOS process steps and package to form microstructure and ensure its stability in physiological saline. The readout circuit is comprised of a current amplifier and an I-V converter and associated with each sensor. A multiplexer is utilized for choosing the working unit.

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