感測器作為物聯網(Internet of Thing, IoT)中最重要的訊息提供者，能夠為系統偵測指定的外界資訊或刺激，從而使系統能做出最恰當的決策。而離子感測器的主要功能就是測量待測溶液中特定離子的濃度，如氫離子 (pH值)、鈉離子以及金屬離子等。另一方面，雖然傳統的離子感測器，如離子感測場效電晶體(Ion-Sensitive Field Effect Transistor, ISFET)已發展臻製成熟，然而，除了靈敏度受限於能斯特極限之外，其臨界電壓(Threshold Voltage)等參數仍會因製程飄移(Process Variation)等非理想效應而造成偏移(Offset)。故為了避免感測錯誤，大部分傳統的離子感測器都需要導入額外的周邊電路或是依靠複雜的演算法，才能消除每個元件之間的偏移。
因此，本研究之宗旨在於開發出兼具低成本、高靈敏度且可靠而不會受偏移影響的離子感測器。故基於臺灣目前領先世界的金屬氧化物半導體場效電晶體(Metal-Oxide-Semiconductor Field-Effect Transistor, MOSFET)科技與積體電路(Integrated Circuit, IC)工業技術，本研究利用先進製程下的浮動閘極結構，將訊號藉由接觸槽的電容耦合機制來控制通道電流，透過該耦合機制即可調節並放大元件靈敏度，同時也能夠提供動態的靈敏度，使本元件能適應於不同的測試環境與應用上。
除此之外，本研究亦首次提出一個基於通道熱電子注入效應(Channel Hot Electron Injection, CHEI)的感測器嵌入式校正方案。透過特定的偏壓設定，浮動閘極所儲存的電荷量將能被控制，故能調節其臨界電壓等參數。由於本嵌入式校正方案不需要額外電路或演算法的輔助，可以有效提高元件可靠度並降低運算與製造成本，從而使本元件在多個領域有極高的應用潛力。

As an important information provider of IoT (Internet of Thing), sensors are the key to detect the signal and stimuli from the environment to ensure a smart system can function at an optimal state. The main function of the ion sensor is to detect the specific ion concentration in the electrolyte solution, most commonly, the pH level. Although the conventional ion sensors using ISFET (Ion-Sensitive Field Effect Transistor) technology have been quite mature, the characteristics of ISFET typically subject to significant variabilities due to the offsets in threshold voltages caused by process variations. To avoid the effect of large variation from device to device, most of the conventional ion sensor rely on the extra circuit or complex algorithm. This problem will cause significant challenge when one tries to implement ISFET arrays for acquiring 2D distribution during the chemical flow.
In this work, a low-cost, highly-sensitive and robust ion sensor with in-cell calibration capability to overcome the offset problem is presented. Through advanced CMOS FinFET technologies, a novel contact coupled floating gate structure is demonstrated to enable an FG-ISFET with high and adjustable sensitivities for embedded sensor applications in advanced circuit systems. To calibrate the variations between devices, the CHEI (Channel Hot Electron Injection) is the first-time proposed to adjust the threshold voltage through an initialization procedure. Through the specific bias condition, the charge stored in the floating gate can be controlled as well as its threshold voltage. Without extra circuit or algorithms, this new sensor can effectively reduce the power and area overheads making it suitable for sensor solutions in IOTs.

摘要 2
Abstract 3
致謝 4
內文目錄 5
圖表目錄 7
第一章 緒論 9
1.1 感測器簡介 10
1.2 研究動機 11
1.3 論文大綱 12
第二章 離子感測器回顧 13
2.1 離子感測機制回顧 13
2.2 傳統離子感測元件回顧 14
2.2.1 離子選擇電極 14
2.2.2 離子感測場效電晶體 14
2.2.3 延伸式閘極離子感測場效電晶體 16
2.3 浮動閘極離子感測場效電晶體 16
2.4 小結 17
第三章 浮動閘極離子感測元件特性與量測 22
3.1 先進製程下之離子感測浮動閘極元件 22
3.1.1 元件結構與特性分析 22
3.1.2 量測環境與設定 24
3.1.3 元件電性量測結果 25
3.2 感測端架構設計與材料分析 27
3.2.1 感測薄膜 27
3.2.2 參考電極 27
3.3 離子感測實驗結果與分析 28
3.3.1 離子感測實驗方法 28
3.3.2 電容耦合效應與靈敏度分析 29
3.3.3 感測薄膜之材料選擇與設計 30
3.3.4 離子感測實時量測結果與雜訊分析 31
3.4 小結 32
第四章 自我平衡之離子感測讀取電路 50
4.1 讀取電路簡介及操作原理 50
4.1.1 回授機制簡介 50
4.1.2 讀取電路設計原理與操作方法 51
4.1.3 讀取電路模擬結果 51
4.2 元件量測結合電路模擬結果分析 52
4.3 小結 53
第五章 新型感測器嵌入式校正方案 59
5.1 感測器陣列原型提案與設計 59
5.2 感測器校正方案 60
5.2.1 感測器校正方案回顧 60
5.2.2 新型感測器嵌入式校正原理 61
5.2.3 感測器校正結果與分析 62
5.3 小結 63
第六章 總結 73
6.1 新型離子感測元件與傳統元件之比較 73
6.2 結語與未來展望 74
參考文獻 77

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