熱電發電器(TEG)是一種可以將熱能直接轉化為電能的裝置，常被應用於廢熱回收的領域上，近年來，利用印刷技術製作的厚膜型熱電發電器具有微型化、低成本且可大量製造的優點，因而被廣泛的研究，本研究著重於利用噴印的方式來製作後模型熱電發電器。首先，我們將熔煉後的P型及N型晶棒以手磨及球磨的方式研磨成細小的粉末，並加入有機溶劑及黏結劑，混合形成可以進行噴印的熱電漿料，再來，我們會將漿料噴印在可撓式的聚醯亞胺基板上，並進行後續的熱壓燒結。在熱壓燒結的部分，我們會分別探討燒結溫度及燒結壓力對於厚膜熱電性質的影響，在進行了最佳化的製程後，我們發現P型及N型厚膜之功率因子分別可達到23.2 及19.1 μW/cmK2。在模組的製備方面，我們將8對熱電接腳噴印在基板，並進行分析。此模組能在溫度差為33 K的條件下產生68 μW的輸出，我們也進行了模組的可靠度測試並將結果與近期的文獻進行比較。最後，我們將7個熱電模組並聯成一模組化熱電發電器，量測分析其輸出效能並探討其可行的應用。

Thermoelectric generation devices are able to convert waste heat into electricity directly. Recently, thick-film thermoelectric devices based on printing technology have been actively researched for their virtues of miniaturization, low cost and mass production. Our work focuses on the fabrication and characterization of thick-film thermoelectric modules prepared by the dispenser printing method. Firstly, the zone-melted p-type Bi0.45Sb1.55Te3Se0.034 and n-type Bi2Te2.7Se0.3 ingots were hand crushed and further refined by planetary ball milling. Afterwards, the fine particles were mixed with the organic solvent and binders to form printable paste. Both p-type and n-type stripes were coated on a polyimide substrate by dispenser printing. Consequently, a hot-press sintering treatment was performed to improve the electrical conductivity of the printed thermoelements. The effects of pressing temperature and pressure on the transport properties of the printed thermoelements are investigated. Our results show that the thermoelectric power factor of p-type and n-type thermoelements can reach 23.2 and 19.1 μW/cmK2, respectively. Moreover, a flexible thermoelectric generator (TEG) composed of 8 pairs of p-n thermoelements was fabricated, which can deliver 68 μW under a temperature difference of 33 K. The performance and stability of the flexible thermoelectric module are also evaluated. Lastly, we produce a modular TEG by integrating 7 thermoelectric modules, measure its output performance and explore its potential applications.

Abstract I
摘要 II
致謝 III
Content IV
List of Figures VI
List of Tables XII
Chapter 1
Introduction 1
1.1 Background 2
1.2 Motivation 7
Chapter 2 Literature review 8
2.1 Thermoelectric thick-film materials 8
2.1.1 Organic thermoelectric thick-film materials 8
2.1.2 Inorganic thermoelectric thick-film materials 10
2.1.3 Hybrid thermoelectric thick-film materials 13
2.2 Fabrication techniques of thermoelectric thick films 17
2.2.1 Screen printing 17
2.2.2 Dispenser printing 19
2.2.3 Inkjet printing 21
2.2.4 Sintering process of thermoelectric thick films 23
2.3 Fabrication and characterization of thermoelectric thick-film devices 27
2.3.1 Advantages of thermoelectric thick-film modules 27
2.3.2 Design considerations of thermoelectric thick-film devices 30
2.3.3 Applications of the thick-film thermoelectric devices 35
Chapter 3 Experimental Procedure 40
3.1 Fabrication of thermoelectric thick films 40
3.2 Hot-pressing process optimization 42
3.2.1 Experimental setting for the hot-pressing process 42
3.2.2 Property measurements of thermoelectric thick films 44
3.3 TEG module fabrication and analysis 48
3.3.1 TEG module design optimization 48
3.3.2 TEG module fabrication 50
3.3.3 TEG module analysis 51
Chapter 4 Results and Discussion 53
4.1 Development of the dispenser printing ink 53
4.1.1 Optimization of the printing ink composition 53
4.1.2 Optimization of the powder volume fraction in the printing ink 55
4.1.3 Dispersion of the printing ink 58
4.2 Sintering optimization of printed TE thick films 60
4.2.1 Sintering pressure effect 60
4.2.2 Sintering temperature effect 62
4.3 Design and analysis of printed TE module 69
4.3.1 Thermoelement length optimization 69
4.3.2 Module output performance 72
4.3.3 Device flexibility 77
4.3.4 Module performance comparison 79
4.3.5 Application demonstration 81
Chapter 5 Conclusions 88
References 90

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