現今半導體產業的迅速發展，晶片在生活中有著舉足輕重的地位，尤其在感測器方面，日常中無時無刻都有它的存在，像是加速度計、觸覺感測器或是光感測器等等，而近年來生醫感測器也逐漸被大家重視，目前許多生醫晶片也與CMOS製程整合，以大幅縮小晶片面積和提高感測度。
本研究以離子感測場效電晶體(Ion Sensitive Field Effect Transistors, ISFET)來進行不同感測電極面積及電晶體尺寸進行DNA感測之探討，總陣列數為16×16個ISFET，其中包括電晶體尺寸3種，感測電極尺寸倍率5種，共15種的排列組合，將量測pH值與B型肝炎病毒DNA在不同種尺寸的特性。
我們在pH值量測中得到最高感測度為電晶體尺寸12 µm/0.5 µm，20倍感測電極（35.61 mV/pH），且感測度隨著感測電極倍率上升而增加，約在20倍以後達到飽和；DNA量測中，我們得到在1X PBS下最高DNA感測度為6 µ/0.5 µ，50倍感測電極（20.36 mV/log10[DNA]），而感測度也是隨著感測電極倍率上升而增加，約在15倍以後達到飽和，且每種尺寸皆會因頻率上升而降低Debye length的遮蔽效應。

With the rapid development of the semiconductor industry in recent years, chips play a crucial role in our daily lives. Especially in the field of sensors, they are ubiquitous, such as accelerometers, tactile sensors, or light sensors. In recent years, biomedical sensors have also been increasingly valued, and many biomedical chips are now integrated with CMOS processes to significantly reduce chip size and improve sensitivity.
This research investigates DNA sensing using ion-sensitive field-effect transistors (ISFETs) with different sensor electrode areas and transistor sizes. The total array consists of 16×16 ISFETs, including three transistor sizes and five magnifications of sensor electrode sizes, resulting in 15 combinations. We measured the pH values and the characteristics of Hepatitis B virus DNA for different sizes.
In pH measurement, we found the highest sensitivity with a transistor size of 12 µ/0.5 µ and a sensor electrode magnification of 20x (35.61 mV/pH). The sensitivity increased with the magnification of the sensor electrode, reaching saturation at around 20x. In DNA measurement, the highest DNA sensitivity in 1X PBS was obtained with a transistor size of 6 µ/0.5 µ and a sensor electrode magnification of 50x (20.36 mV/log10[DNA]). The sensitivity also increased with the magnification of the sensor electrode, reaching saturation at around 15x. Additionally, each size showed a decrease in the Debye length shielding effect as the frequency increased.

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