在這個半導體產業迅速發展的時代，晶片的設計結合了人類生活的應用，日常中感測器與我們形影不離，例如:觸覺感測器、生物感測器、氣體感測器、光感測器、聲音感測器、動態感測器等等，而近年來由於疫情的影響，為了能更快速且便利的檢測病毒和疾病，生醫感測器更是一個熱門的應用，利用可以與CMOS製程整合的電路設計，結合電化學的應用，製作出微機電系統整合的晶片，可大幅縮小感測器尺寸且提高精準度。
本研究使用延伸電極場效電晶體(Extended Gate Field Effect Transistors, EGFET)作為感測元件，檢測相似於人體血液濃度中的B型肝炎病毒DNA 載量(fM等級)，透過將化學訊號轉為電路訊號以此作為感測機制，但由於在接近人體血液濃度中會有因溶液中離子所造成的電荷遮蔽效應，此效應會使得感測訊號受到干擾，因此如何解決電荷遮蔽的效應便是本研究一個重要的課題。我們搭配電路設計，設計一個3232的感測陣列，特色為每個感測器的尺寸小，且為了將低晶片功耗，我們僅使用一組輸出電路，並透過將電路操作在高頻，試著打破在高離子溶液環境下電荷遮蔽的效應，提高在高離子溶液環境中對於B型肝炎(Hepatitis B virus) DNA(deoxyribonucleic acid)的感測度。在不同pH值緩衝溶液下，我們量測到pH值的感測度為37.5mV/pH。而B型肝炎DNA的量測，我們感測〖10〗^(-16)M~〖10〗^(-8)M的DNA分子，在0.01XPBS溶液下，EGFET的臨界電壓變化為17.2 mV/〖/log〗_10[DNA]；在1XPBS溶液下，EGFET的臨界電壓變化為19.3 mV/〖/log〗_10[DNA]。

In this era of rapid development of the semiconductor industry, the applications of chip design have high connection with human life. Sensors are inseparable from us in everyday life. Tactile sensor, biological sensor, gas sensor, light sensor, sound sensor, motion sensor and many other sensors are wildly used in our daily life. Especially nowadays we suffered from pandemic, biomedical sensors highlight its value in order to detect viruses and diseases more quickly and conveniently. By integrating the CMOS circuit process and MEMS on the same chip, we can produce biomedical sensor chips with small size and high accuracy.
In this paper, we use Extended Gate Field Effect Transistors (EGFET) as our sensing element to detect very low concentrations of hepatitis B virus DNA load (fM grade) in blood. This detection method is based on converting chemical signals to electrical signals. However, detected signal in the sample solution similar to blood is limited by the ion-screening effect caused in sample solution with high ion concentration. Therefore, how to break through the limitations of biomedical sensing is an important issue in our research.
In terms of design, in order to breakthrough Debye length effect of charge screening effect in sample solution with high ion concentration, an 3232 sensor array with small pixel size and low power consumption has been developed. The high-frequency modulation is effective to reduce charge screening so as to improve the sensitivity of the sensor. In the sensing of different pH standard solutions, we measured the sensitivity of pH value to be 35.7mV/pH.In addition, we also added DNA of Hepatitis B virus for sensing DNA molecules with a concentration of 〖10〗^(-16)M~〖10〗^(-8)M.The threshold voltage change of EGFET measured in 0.01X PBS buffer solution is 17.2 mV/〖/log〗_10[DNA] and in 1X PBS buffer solution is 19.3 mV/〖/log〗_10[DNA].

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