臺灣博碩士論文加值系統

本論文研究探討具氧化鉬及氧化亞銅堆疊層與氧化鉬銅電洞選擇性接觸層之單晶矽太陽能電池光電特性研究，過渡金屬氧化物常用於載子選擇性接觸層，其中，二氧化鉬因其製程溫度低、有較大的功函數以及良好的電子阻擋特性，是很好的電洞選擇性接觸層材料，因此藉由改善電洞選擇性接處層的特性，進一步提升單晶矽太陽能電池的光電轉換效率、開路電壓及短路電流。首先探討厚度對具單層氧化鉬及單層氧化亞銅太陽能電池的光電特性影響，接著，比較了具有銀電極和銅電極的單晶矽太陽能電池的光電效應，再分別用銅顆粒及氧化亞銅顆粒，與氧化鉬形成共蒸鍍層和堆疊結構，並改變了結構的厚度及破真空時機，探討最佳的結構及厚度，最後利用穿透式電子顯微鏡與能量色散光譜儀量測結構的厚度及元素組成。
實驗結果顯示，用銅顆粒作為源材料的單晶矽太陽能電池，不論是與氧化鉬共蒸鍍，或者與氧化鉬堆疊，轉換效率都沒有很好。若結構為蒸鍍氧化鉬堆疊氧化亞銅，當氧化鉬厚度6 nm、氧化亞銅厚度0.75 nm、破真空時間5分鐘，且搭配銀電極500 nm時，元件有最佳平均光電轉換效率21.76 %，其開路電壓0.66 V、短路電流40.90 mA/cm2、填充因子81.23 %及串聯電阻1.6 Ω-cm2。另外，關於氧化亞銅顆粒與氧化鉬共蒸鍍形成的氧化鉬銅，當厚度為3.8 nm時，元件有最佳平均光電轉換效率21.08 %，其開路電壓0.65 V、短路電流40.91 mA/cm2、填充因子79.19 %及串聯電阻1.88 Ω-cm2。綜合上述實驗結果得知，比起具單層氧化鉬的單晶矽太陽能電池，具氧化鉬/氧化亞銅堆疊層的單晶矽太陽能電池的轉換效率較佳。

In this thesis, photovoltaic properties of monocrystalline silicon solar cells (MSSCs) with molybdenum oxide /cuprous oxide (MoOx/CuOx) stacked layers and molybdenum copper oxide (MoCuxOy) hole-selective contact layers (HSCLs) were investigated. Transition metal oxides are often used in carrier-selective contact layers. Among them, MoOx is a good HSCL material because of its low process temperature, large work function and good electron blocking characteristics. Therefore, the conversion efficiency (CE), open-circuit voltage (Voc), and short-circuit current (Jsc) of the MSSCs were further improved by turning HSCL characteristics. Firstly, the influence of the thickness on the photovoltaic characteristics of MSSCs with single-layer MoOx and CuOx was discussed, respectively. Then, the photovoltaic effects of MSSCs with silver and copper electrodes were compared. Copper particles and CuOx particles are used, respectively, to form co-evaporated layers and stacked structures with molybdenum oxide. Moreover, the thickness of the structures and the timing of the broken vacuum were changed, as well as the optimal structure and thickness were discussed. Finally, the thickness and elemental composition of the structure were measured using a transmission electron microscope (TEM) and energy dispersive spectroscopy (EDS).
The results indicated that the CEs of MSSCs formed by copper particles as the source material were not well, whether it was co-evaporated with MoOx or stacked. If the MoOx/CuOx stacked structure was formed at the MoOx of 6 nm, CuOx of 0.75 nm, the broken vacuum time of 5 minutes, and the Ag electrode of 500 nm, the MSSCs with the best CE of 21.76 %, Voc of 0.66 V, Jsc of 40.90 mA/cm2, fill factor (FF) of 81.23 % and series resistance (Rs) of 1.6 Ω-cm2, were demonstrated. Furthermore, the MSSCs with the CE of 21.08 %, Voc of 0.65 V, Jsc of 40.91 mA/cm2, FF of 79.19 % and Rs of 1.88 Ω-cm2, were achieved by the MoCuxOy with 3.8 nm formed at the co-evaporation of CuOx particles and MoOx. According to the above experimental results, it can be concluded that the CE of MSSC with MoOx/CuOx stacked film was better than that of the MSSCs with a single layer of MoOx.

摘要...............i
Abstract..........ii
誌謝..............iii
目錄..............iv
表目錄............vii
圖目錄...........viii
第一章 緒論........1
1.1氧化鉬電洞選擇性接觸層應用於太陽能電池之文獻回顧........1
1.2氧化亞銅電洞選擇性接觸層應用於太陽能電池之文獻回顧......2
1.3氧化鉬銅應用於太陽能電池之文獻回顧...............4
1.4研究動機...........5
1.5論文架構.............5
第二章 實驗流程介紹及實驗參數.............6
2.1改變電洞選擇性接觸層參數實驗之前段製程...........6
2.1.1 利用標準清洗法去除矽基板表面塵粒以及自然氧化層...........6
2.1.2 藉由鹼性溶液氫氧化鉀作為主蝕刻液搭配去離子水及異丙醇對矽基板進行糙化...7
2.1.3 利用高溫爐管在矽基板上進行磷擴散以形成n+射極層...........7
2.1.4 透過退火製程消除缺陷和降低應力提升結晶品質..........7
2.1.5 利用酸性混合液去除磷玻璃與邊緣隔絕..........8
2.1.6使用電漿增強化學氣相沉積法在正面沉積氮化矽層作為抗反射層...........8
2.1.7藉由網印技術將銀膠網印至正面並烤乾.................8
2.1.8 使用網帶式紅外加熱快速燒結爐對矽基版進行燒結................8
2.1.9使用雷射切割機將單晶矽基板切割成2 cm × 2 cm大小..................9
2.2蒸鍍氧化鉬厚度效應................9
2.2.1利用旋轉塗佈機將聚合物膠塗於矽晶片正面並烤乾...................9
2.2.2利用稀釋過的氫氟酸蝕刻背表面的自然氧化層...........9
2.2.3 熱蒸鍍氧化鉬於矽晶片背面...............9
2.2.4 熱蒸鍍銀電極於矽晶片背面..................10
2.2.5 電流-電壓特性量測................10
2.3蒸鍍氧化亞銅厚度及其破真空效應...............10
2.3.1利用旋轉塗佈機將聚合物膠塗於矽晶片正面並烤乾...............10
2.3.2利用稀釋過的氫氟酸蝕刻背表面的自然氧化層.....................10
2.3.3 熱蒸鍍氧化亞銅於矽晶片背面.................11
2.3.4 熱蒸鍍銀電極於矽晶片背面....................11
2.3.5 電流-電壓特性量測...................11
2.4探討銀及銅電極對氧化鉬/氧化鉬銅堆疊層及氧化鉬效應.................11
2.4.1利用旋轉塗佈機將聚合物膠塗於矽晶片正面並烤乾................11
2.4.2利用稀釋過的氫氟酸蝕刻背表面的自然氧化層................12
2.4.3熱蒸鍍接觸層於矽晶片背面................12
2.4.4熱蒸鍍金屬電極於矽晶片背面.............12
2.4.5電流-電壓特性量測..................12
2.5銅共蒸氧化鉬之氧化鉬銅在氧化鉬層內之上、中、下層堆疊結構效應..........13
2.5.1利用旋轉塗佈機將聚合物膠塗於矽晶片正面並烤乾........13
2.5.2利用稀釋過的氫氟酸蝕刻背表面的自然氧化層.............13
2.5.3熱蒸鍍接觸層於矽晶片背面..............13
2.5.4熱蒸鍍銀電極於矽晶片背面...............14
2.5.5電流-電壓特性量測.............14
2.6氧化鉬/銅共蒸氧化鉬形成氧化鉬銅堆疊層中氧化鉬厚度效應..................14
2.6.1利用旋轉塗佈機將聚合物膠塗於矽晶片正面並烤乾................14
2.6.2利用稀釋過的氫氟酸蝕刻背表面的自然氧化層...............14
2.6.3熱蒸鍍氧化鉬/銅共蒸氧化鉬形成氧化鉬銅堆疊層於矽晶片背面............15
2.6.4熱蒸鍍銀電極於矽晶片背面.............15
2.6.5電流-電壓特性量測............15
2.7比較氧化鉬及氧化亞銅之破真空效應...........15
2.7.1利用旋轉塗佈機將聚合物膠塗於矽晶片正面並烤乾..........15
2.7.2利用稀釋過的氫氟酸蝕刻背表面的自然氧化層.................16
2.7.3熱蒸鍍氧化鉬及氧化亞銅於矽晶片背面.................16
2.7.4熱蒸鍍銀電極於矽晶片背面.................16
2.7.5電流-電壓特性量測...............16
2.8蒸鍍氧化鉬/氧化亞銅堆疊層及其厚度效應...............17
2.8.1利用旋轉塗佈機將聚合物膠塗於矽晶片正面並烤乾...........17
2.8.2利用稀釋過的氫氟酸蝕刻背表面的自然氧化層...........17
2.8.3於矽晶片背面熱蒸鍍氧化鉬破真空後熱蒸鍍氧化亞銅........17
2.8.4熱蒸鍍銀電極於矽晶片背面..........18
2.8.5電流-電壓特性量測.............18
2.8.6穿透式電子顯微鏡之材料分析...........18
2.8.7能量色散光譜儀之材料分析............18
2.9不同材料共蒸形成之氧化鉬銅比較............18
2.9.1利用旋轉塗佈機將聚合物膠塗於矽晶片正面並烤乾..........18
2.9.2利用稀釋過的氫氟酸蝕刻背表面的自然氧化層.........19
2.9.3熱蒸鍍氧化鉬銅於矽晶片背面並破真空.............19
2.9.4熱蒸鍍銀電極於矽晶片背面..............19
2.9.5電流-電壓特性量測..............19
2.9.6穿透式電子顯微鏡之材料分析........20
2.9.7能量色散光譜儀之材料分析.......20
第三章 具氧化鉬及氧化亞銅堆疊層與氧化鉬銅電洞選擇性接觸層之單晶矽太陽能電池光電特性研究............38
3.1 蒸鍍氧化鉬厚度效應.............38
3.1.1蒸鍍氧化鉬厚度效應之電流-電壓量測分析.............38
3.1.2結果與討論..........38
3.2 蒸鍍氧化亞銅厚度及其破真空效應............39
3.2.1蒸鍍氧化亞銅厚度及其破真空效應之電流-電壓量測分析........39
3.2.2 結果與討論............39
3.3 探討銀、銅電極對氧化鉬/氧化鉬銅堆疊層及氧化鉬效應.............40
3.3.1 探討銀、銅電極對氧化鉬/氧化鉬銅堆疊層及氧化鉬效應之電流-電壓量測分析.......40
3.3.2 結果與討論...........40
3.4 銅共蒸氧化鉬形成之氧化鉬銅在氧化鉬層之上、中、下層結構效應........41
3.4.1 銅共蒸氧化鉬形成之氧化鉬銅在氧化鉬層之上、中、下層結構效應之電流-電壓量測分析...........41
3.4.2 結果與討論...........42
3.5 氧化鉬/銅共蒸氧化鉬形成氧化鉬銅堆疊層及其厚度對元件效應.........42
3.5.1 氧化鉬/銅共蒸氧化鉬形成氧化鉬銅堆疊層及其厚度對元件效應之電流-電壓量測分析............42
3.5.2 結果與討論............43
3.6 比較氧化鉬及氧化亞銅破真空效應................43
3.6.1 比較氧化鉬及氧化亞銅破真空效應之電流-電壓量測分析............43
3.6.2 結果與討論..........44
3.7 蒸鍍氧化鉬/氧化亞銅堆疊層及其厚度效應................44
3.7.1 蒸鍍氧化鉬/氧化亞銅堆疊層及其厚度效應之電流-電壓量測分析........44
3.7.2 蒸鍍氧化鉬/氧化亞銅堆疊層及其厚度效應之材料分析.........45
3.7.3 結果與討論...........45
3.8 不同材料共蒸形成之氧化鉬銅比較.........45
3.8.1 不同材料共蒸形成之氧化鉬銅比較之電流-電壓量測分析..........46
3.8.2 不同材料共蒸形成之氧化鉬銅比較之材料分析..................46
3.8.3 結果與討論................47
第四章 總結論與未來展望..........83
4.1 總結論.................83
4.2 未來展望...............83
參考文獻...................84
Extended Abstract.........87

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