隨著科技的進步，人們的生活也愈來愈便利，使得我們可以從世界各地獲取各式各樣的資訊；但也因為如此，各種文明病也不斷地發生在人們身上，生活上的便利常伴隨而來的是生活上的壓力，當壓力過大的時候，則會對人們的健康造成影響。人體中的離子濃度變化能直接反映人體健康與否的因素，過高或過低的許多離子濃度都分別顯示會與許多疾病相關。所以如果能即時監控人體中的許多離子濃度，則對於許多疾病的預防及治療將會有很大的助益。
為了發展出一種可快速的同時檢測人體中許多重要離子濃度的新型微系統，數個不同的微型離子感測器必須整合到同一片晶片上，並且搭配一個共用的微型參考電極晶片，如此方能進一步結合訊號讀取電路而開發出可攜式微型離子檢測系統。本論文運用微機電製程技術開發出五個位於同一晶片上的延伸式閘極場效電晶體，並分別將五種不同的離子感測薄膜(分別為鈉、鈣、氯、銨及鉀離子)分別沉積於閘極感測區域上，以完成單晶片式多重離子感測陣列之開發；其次，為了達成整個離子感測系統的微型化及可攜式化，所設計與製作完成的鈉/鈣/氯/銨/鉀多重離子感測陣列晶片還需要整合另一個微型參考電極晶片之開發。本論文運用微機電製程技術所開發之微型參考電極晶片的尺寸僅僅只有9 mm (W)× 6 mm(L) × 1 mm (H)，該晶片包含鈦/銀/氯化銀之電極晶片與具備塗注有氯化鉀凝膠於背面矽腔體之封裝晶片兩大部分；另一方面，本論文所設計開發的延伸式閘極場效電晶體元件之寬長比1000 μm/10 μm，且其感測區域面積為1 mm × 1 mm，而五個離子感測器可以整合在一個1.3 cm (W) × 1.1 cm (L) × 1 mm (H)的矽晶片上。
根據量測結果顯示，本論文所開發之鈉/鈣/氯/銨/鉀多重離子感測陣列具有高感測靈敏度(鈉：38 mV/pNa；鈣：36.7 mV/pCa；氯：56.7 mV/pCl；銨：323 mV/ pNH4 at pNH4 1~1.3、22.2 mV/ pNH4 at pNH4 1.3~4；鉀：48 mV/pK)、高感測線性度(鈉：0.985；鈣：0.941；氯：0.932；銨：0.999 at pNH4 1~1.3、0.990 at pNH4 1.3~4；鉀：99.9%)、低遲滯電壓(鈉：13 mV at pNa 2.6；鈣：10 mV at pCa 2.6；氯：7 mV at pCl 1.3；銨：15 mV at pNH4 1.3；鉀：6 mV at pK 2)、高使用壽命(大於30天)以及低反應時間(約180秒)等優異特性，非常適合應用於可攜式即時檢測之多重離子感測微系統中。另一方面，本論文所開發之鈦/銀/氯化銀/氯化鉀凝膠之微型參考電極晶片具有高穩定性(經三萬秒測試時間，電位僅飄移2.3 mV)的特性，其性能已趨近於商用之參考電極，故可提供多重離子感測陣列晶片一個不受待測溶液離子變化影響之穩定參考電位。

With the advance of science and technology, our life has become more and more convenient. We can receive large amount of information from around the world. But also because of this, a lot of civilization diseases appears in modern life (e.g., the pressure of life often accompanied by the convenient life) and will result in poor health conditions of human body. The concentration of ions in human blood not only respond directly to health condition, but also can obtain symptoms of different diseases by detecting it.
In order to develop a novel microsystem that can detect the concentration of different ions rapidly at the same time, several different ion sensors must be integrated on one chip. A common micro reference electrode is also needed to be combined together to develop the portable micro multi-ion detection system. Five extended-gate field-effect transistor (EGFET) devices are fabricated on one chip by utilizing micro-electromechanical systems (MEMS) in this thesis. Five different ion selective membranes (ISMs) which can adsorb the appointed ions are coated on each separate gate metal electrodes of the EGFETs to develop the sodium, calcium, ammonium, chloride and potassium ion sensors array. To obtain the miniaturization and portable ion detection system, a planar solid-state Ti/Ag/AgCl/KCl-gel reference electrode (μRE) is also developed in this study. The size of the proposed μRE also fabricated by utilizing MEMS is only 9 mm (W) × 6 mm (L) × 1 mm (H). The μRE includes two parts: a Ti/Ag/AgCl electrode chip and a packaging chip with the KCl-gel injected on the backside silicon cave. On the other hand, the channel width/length ratio of the implemented EGFET device is 1000 μm/10 μm and the extended gate sensing area is 1 mm × 1 mm. Five EGFET devices are integrated on the silicon chip with a volume of 1.3 cm (W) × 1.1 cm (L) × 1 mm (H).
Based on the measurement results, the proposed multi-ion sensors array have excellent characteristics with high sensitivity (Sodium：38 mV/pNa, Calcium：36.7 mV/pCa, Chloride：56.7 mV/pCl, Ammonium：323 mV/ pNH4 at pNH4 1~1.3 and 22.2 mV/ pNH4 at pNH4 1.3~4, Potassium：48 mV/pK), high sensing linearity (Sodium：0.985, Calcium：0.941, Chloride：0.932, Ammonium：0.999 at pNH4 1~1.3 and 0.990 mV/ pNH4 at pNH4 1.3~4, Potassium：99.9%), low hysteresis voltage (Sodium：13 mV at pNa 2.6, Calcium：10 mV at pCa 2.6, Chloride：7 mV at pCl 1.3, Ammonium：15 mV at pNH4 1.3, Potassium：6 mV at pK 2), long life time (more than 30 days) and short response time (about 180 seconds). It is very suitable for the application of the portable multi-ions detection microsystem. Besides, the implemented Ti/Ag/AgCl/KCl-gel μRE has good characteristics with low drift voltage, which are almost the same as that of the commercial reference electrode. Hence, the proposed μRE can provide the multi-ions sensors array with a stable reference potential.

論文審定書 i
誌謝 iii
中文摘要 iv
Abstract vi
Contents ix
List of Figures xii
List of Tables xvii
Chapter 1 Introduction 1
1.1 Research Motivation 1
1.2 Ion Sensors 3
1.2.1 Ion-selective Electrode 4
1.2.2 Ion-sensitive Field-effect Transistor 6
1.2.3 Extended-gate Field-effect Transistor 7
1.3 Solid-state Reference Electrode 8
Chapter 2 Theory Description 11
2.1 EIS Structure 11
2.2 Double Layer 14
2.3 Site-binding Model 17
Chapter 3 Development of the EGFET-based Multi-ion Sensor 23
3.1 Layout Design of the Proposed EGFET Device 25
3.2 Fabrication of the Proposed EGFET Device 27
3.3 Encapsulation of the silicon-based packaging chip 30
3.4 Preparation of ISMs 32
3.4.1 ISM of Sodium Ion Sensor 32
3.4.2 ISM of Calcium Ion Sensor 32
3.4.3 ISM of Chloride Ion Sensor 32
3.4.4 ISM of Ammonium Ion Sensor 32
3.4.5 ISM of Potassium Ion Sensor 33
3.5 Fabrication of the Planar Solid-state Reference Electrode 33
3.6 Measurement Setup 39
Chapter 4 Results and Discussion 41
4.1 Characterization of the EGFET Device 42
4.2 Characterization of the Planar μRE 43
4.3 Characterization of the EGFET-based Multi-ion Sensor 47
4.3.1 Sensitivity and Linearity 47
4.3.2 Hysteresis 54
4.3.3 Selectivity 58
4.3.4 Lifetime 59
Chapter 5 Conclusions and Future Works 62
5.1 Conclusions 62
5.2 Future Works 63
Reference 65
Personal Publication 76

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