受惠於半導體工業的發展，電路設計是非常成熟的產業，將電路與微機電整合在同一塊晶片上，可以製作出快速以及高感測度的生醫感測器，靠不同的表面修飾方法，可以感測不同的細胞或是生物分子。
本論文設計指叉式感測電極以及平板式感測電極，預期當生物分子被修飾在電極上方的氧化層(SiO_2)時，由於分子在電場作用下產生的極化效應，感測電極的電容值會有對應的變化，這個變化可以藉由感測電路讀出。另外我們設計第三種電極，在指叉電極下方放置一塊平板電極，藉由給定平板電極不同的電壓來量測DNA的電容值變化。
本論文探討的重點在於，藉由使用指叉式電極以及平板式電極對於電容式DNA感測器的感測度探討電容式感測的機制。實驗上，我們完成了濃度從1 aM至1 pM的DNA感測，在這個範圍中電容式感測器的電容值變化了約40 %。

Benefited from the development of the semiconductor industry, circuit design has become a very mature industry. With the integration of circuits and micro-electromechanical devices on the same chip, we can produce a rapid and high sensitivity biomedical sensor. Depending on the surface modification method, we can sense different cells or biological molecules.
The chip design contains both the interdigitated electrodes and planar electrodes,. It is expected that when the DNA is modified on the oxide layer (SiO2) above the electrodes, the capacitance value of the sensing electrode will have a corresponding change due to the polarization effect produced by the molecules under the electric field. This change can be readout by the sensing circuit. In addition, a third planar electrode is placed under the interdigitated electrodes to apply different biases for monitoring the capacitive changes associated with the hybridized DNA.
The focus of this work is to explore the mechanism of capacitive sensing of interdigitated and planar electrodes. In experiments, we performed DNA sensing at concentrations ranging from about 1 aM to 1 pM in which the capacitance varied by about 40 %.

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