本實驗室使用獨特的垂直式通道結構，以溶液製程的金屬鹵化物鈣鈦礦半導體材料製作成氣體感測器。我們可以發現，垂直式通道結構和傳統的水平電極結構互相比較，可以提升電流以及訊號雜訊比，也因此，我們看到鈣鈦礦材料可以偵測到ppb(parts-per-billion)等級的一氧化碳(CO)氣體，而且此偵測的環境是在大氣背景下完成！這個結果開啟了許多有趣的想法，例如，我們好奇這樣的氣體偵測是由於鈣鈦礦材料與氣體的反應，或是金屬半導體接面能障在氣體吸附時出現了變化呢?當調整鈣鈦礦材料的成分組成，以及更改電極的材料時，我們是否能夠調製出對不同氣體有不同感測能力的元件呢?
所以我們將延續垂直通道元件結構，我們將調整鈣鈦礦材料的鹵素比例以及薄膜結晶尺寸，表面形貌等，來探討元件對氣體的反應；為了瞭解金屬半導體接面扮演的角色，我們也將改變金屬功函數，了解蕭基接觸狀況下注入能障對感測的影響，觀察是否可進一步提升感測靈敏度，因為目前鈣鈦礦材料在空氣中的穩定性只有數個小時，我們也期望能改善此元件的穩定性，利用有機無機混摻半導體層或多層半導體結構，來改善鈣鈦礦氣體感測器的穩定性。

we try to fabricated perovskite gas sensor with a unique vertical channel structure. In our result, we already observed that the vertical channel perovskite device exhibited a large current and hence improved the signal-to-noise ratio. The device has an obvious response to carbon mono-oxide (CO) in parts-per-billium (ppb) regime. It is noted that the background is ambient air!! With this sucessful preliminary result, we then like to perform a systematic study to investigate the underlying mechanism of the perovskite gas sensor.
Based on the vertical channel structure, we like to observe the gas sensing behavior when changing the composition and the grain size of perovskite thin film. To verify if the sensing is related to the metal/semiconductor interface, we will use different metals (or conductive oxide with interface treatment) to modulate the workfunciton of injected electrode and then to study the influence of Schottky contact barrier on gas sensing. Moreover, we like to tune the injection to try allow only electron or only hole in the conduction path, hopefully to improve sensitivity by using the uni-carrier conduction. Finally, we also like to test the influence of a blended composite film (mixing perovskite and organic semiconductor) on gas sensing. Particularly, we like to find suitable film composition to improve the sensor lifetime in air ambient operation.

致謝 v
圖目錄 3
表目錄 6
Chapter1 緒論 7
1-1前言 7
1-2研究動機 9
1-2-1金屬鹵素鈣鈦礦材料優勢 9
1-2-2金屬鹵素鈣鈦礦氣體感測研究概況 11
1-3論文架構 13
Chapter2 有機材料及金屬鹵素鈣鈦礦介紹及元件操作原理 14
2-1有機材料特性及金屬鹵素鈣鈦礦材料介紹 14
2-1-1有機材料特性介紹 14
2-1-2金屬鹵素鈣鈦礦材料製程介紹 14
2-2金屬鹵素鈣鈦礦材料氣體感測機制 16
2-3有機半導體與金屬接面探討 17
2-4有機二極體物理介紹 19
2-4-1熱離子發射理論 19
2-4-2穿隧效應理論 20
2-4-3塊材限制理論 20
Chapter3 金屬鹵素鈣鈦礦氣體感測器元件製程 22
3-1標準製程定義圖樣 22
3-2水平及垂直指叉式電極金屬鹵素鈣鈦礦感測器之製程 24
3-2-1水平指叉式電極元件 24
3-2-2垂直指叉式電極元件 26
3-3氣體量測系統介紹 29
Chapter4金屬鹵素鈣鈦礦氣體感測器之應用 30
4-1探討鈣鈦礦在玻璃和ITO上成膜之差異 30
4-2有無反溶劑及反溶劑溶劑對於鈣鈦礦成膜影響 31
4-3垂直與水平指叉式電極鈣鈦礦氣體感測器比較 32
4-3-1垂直與水平指叉式電極鈣鈦礦在大氣下表面及電性衰退比較 33
4-3-2垂直與水平指叉式電極鈣鈦礦氣體感測比較探討 35
4-4垂直指叉式電極鈣鈦礦置換鹵素根之比較 36
4-4-1垂直指叉式電極純碘鈣鈦礦 36
4-4-2垂直指叉式電極純溴鈣鈦礦 37
4-4-3垂直指叉式電極溴氯混和鈣鈦礦 38
4-4-4比較不同鹵素根垂直指叉式電極鈣鈦礦探討 39
4-5垂直指叉式電極鈣鈦礦感測器表面覆蓋層及注入層改善 40
4-5-1垂直指叉式電極鈣鈦礦感測器覆蓋PCBM 41
4-5-2垂直指叉式電極鈣鈦礦感測器添加注入層PEG 42
4-5-3通道覆蓋DMSO載氣之測試 43
4-6蒸鍍不同金屬電極對純碘鈣鈦礦感測器之影響 44
4-6-1鋁電極之垂直指叉式純碘鈣鈦礦感測器 45
4-6-2鋁/MoO3電極之垂直指叉式純碘鈣鈦礦感測器 46
4-6-3鋁/LiF電極之垂直指叉式純碘鈣鈦礦感測器 47
4-6-4Cr/Au電極之垂直指叉式純碘鈣鈦礦感測器 48
4-6-5統整不同金屬電極之垂直指叉式鈣鈦礦感測器 49
4-7轉速優化金屬鹵素鈣鈦礦膜面結果 51
Chapter5 結論及未來展望 53
5-1結論 53
5-2未來展望 54
參考文獻 55

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