臺灣博碩士論文加值系統

本論文研究探討氧化鉬電洞選擇性傳輸層的熱處理與堆疊效應對網印式單晶矽太陽能電池之光電特性研究，目前射極鈍化與背接觸式單晶矽太陽能電池(Passivated Emitter and Rear Cell: PERC)的背面結構主要為沉積一層氧化鋁(AlOx)鈍化層搭配沉積氮化矽層(SiNx)阻障層，因為氧化鋁與氮化矽堆疊層為絕緣層，因此需要雷射製程，對氧化鋁鈍化層與氮化矽阻障層進行雷射開孔製程，以利於鋁膠能與矽基板接觸形成背電場，然而雷射開孔會對矽基板表面造成損傷，因此本研究採用蒸鍍氧化鉬電洞選擇性傳輸層取代氧化鋁與氮化矽堆疊層，其好處可避免雷射開孔製程造成的表面損傷，又免於使用電漿輔助化學氣相沉積製程(PECVD) 沉積氮化矽層。首先探討蒸鍍完氧化鉬後的抽真空時間效應，對銀電極的影響，接著研究二氧化鉬與三氧化鉬堆疊順序、三氧化鎢與三氧化鉬堆疊順序，再對二氧化鉬與三氧化鉬不同厚度堆疊之特性研究，最後探討在蒸鍍完單層二氧化鉬後，對二氧化鉬薄膜進行不同氣體、溫度與加熱時間的熱處理效應。
實驗結果顯示，當蒸鍍完氧化鉬後其抽真空時間越短，對太陽能電池之光電轉換效率影響不大，甚至蒸鍍完氧化鉬後直接蒸鍍銀電極，光電轉換效率有些微提升，因此在考慮縮短製程時間的情形下，後續實驗皆採用蒸鍍完氧化鉬電洞選擇性傳輸層後，直接蒸鍍銀電極，在堆疊不同電洞選擇性傳輸層時，二氧化鉬與三氧化鉬堆疊層比其他堆疊層較佳，且蒸鍍完一層後，破真空再接續蒸鍍另一種電洞選擇性傳輸層與銀電極，比直接蒸鍍兩種電洞選擇性傳輸層，破真空後再蒸鍍銀電極有較好之光電轉換效率，最後對單層二氧化鉬在不同的氣體下進行不同溫度與時間的熱處理，當熱處理氣體為氮氣且溫度為100 ℃時，加熱時間為5分鐘時，有最佳太陽能電池之光電轉換效率為18.5 %。

In this thesis, the effects of thermal treated and stacked molybdenum oxide hole-selective transfer layers on photovoltaic characteristics of screen-printed monocrystalline silicon solar cells (SPMSSCs) were investigated. The backside structures of passivated emitter and rear cells (PERCs) were presented by aluminium oxide (AlOx) and silicon nitride (SiNx) as passivation and diffusion layer, respectively. Since aluminium oxide and silicon nitride were insulator layer, aluminium oxide/silicon nitride stacked films were needed to form the contact holes using laser process for screen-printed Al pastes and silicon substrate contact. However, the laser damage can be formed by laser process. Thus, in this work, aluminium oxide and silicon nitride stacked films were replaced by thermal evaporated molybdenum oxide (MoOx) as the hole-selective transfer layers. The advantages of thermal evaporated MoOx were without laser process and silicon nitride formed by plasma-enhanced chemical-vapor-deposition. First, the effects of waiting time in vacuum after evaporated MoO2 on silver electrode were investigated. Next, the effects of the MoO2/MoO3 and WO3/MoO3 stacked films and sequence were investigated. Furthermore, the effects of thickness of MoO2 and MoO3 stacked films were investigated. Finally, the thermal treated MoO2 with various gas ambient, temperatures, and time were addressed.
The results show that the conversion efficiency (CE) of the SPMSSCs can be slightly increased by shorter waiting time in vacuum ambient. In order to reduce the manufacturing time, the silver electrode was deposited immediately after deposition of the hole-selective transfer layers. The photovoltaic characteristics of the MoO2/MoO3 staked film was better than that of the other stacked films. The CEs of stacked films with deposition-broke vacuum-deposition-deposition in sequence were better than that of the deposition-deposition- broke vacuum-deposition in sequence ones. Finally, The CE with 18.5 % was presented by the MoO2 treated at 100 oC for 5 min in N2 ambient.

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射極鈍化與背接觸式單晶矽太陽能電池背面局部雷射損傷之文獻回顧..........1
1.2載子選擇性傳輸層應用於太陽能電池之文獻回顧..........2
1.3氧化鉬各種處理與堆疊效應之文獻回顧..........4
1.4研究動機..........5
1.5論文架構..........5
第二章 實驗流程與特性量測..........6
2.1氧化鉬電洞選擇性傳輸層的熱處理與堆疊效應對網印式單晶矽太陽能電池之光電特性研究的製作流程與元件特性量測..........6
2.1.1藉由鹼性濕蝕刻對表面進行粗糙化(Texturing)..........6
2.1.2藉由高溫爐管進行正面射極磷擴散(Phosphorus diffusion)..........6
2.1.3藉由DHF藥液移除磷矽玻璃(PSG removed)..........6
2.1.4藉由PECVD沉積正面氮化矽抗反射層(ARC deposition)..........6
2.1.5藉由雷射切割將試片切成面積2x2 cm2的試片(Laser cutting)..........7
2.1.6網印正電極銀膠(Screen-printing)..........7
2.1.7藉由高溫燒結技術形成正電極(Firing)..........7
2.1.8正面旋塗兩層抗蝕刻阻擋膠(Spin coating polymer)..........7
2.1.9藉由DHF藥液移除背面原生氧化層(Removed native oxide)..........7
2.1.10背面熱蒸鍍二氧化鉬(Thermal evaporated MoO2)..........7
2.1.11接續抽真空..........8
2.1.12破真空(Breaking vacuum)..........8
2.1.13背面熱蒸鍍三氧化鉬(Thermal evaporated MoO3)..........8
2.1.14背面熱蒸鍍三氧化鎢(Thermal evaporated WO3)..........8
2.1.15通入氣體(Gas)..........8
2.1.16熱處理(Thermal treated)..........8
2.1.17熱蒸鍍背銀電極(Thermal evaporated Ag)..........8
2.1.18氧化鉬太陽能光伏元件之電性量測(I-V measurement)..........8
2.1.19元件外部量子效率量測(EQE measurement)...............9
2.2探討蒸鍍完二氧化鉬層的抽真空效應對網印式單晶矽太陽能電池之特性影響..........9
2.3探討二氧化鉬與三氧化鉬堆疊順序效應、三氧化鎢與三氧化鉬堆疊順序效應、二氧化鉬與三氧化鉬不同厚度堆疊效應對網印式單晶矽太陽能電池之光電特性影響..........9
2.3.1探討二氧化鉬與三氧化鉬堆疊順序效應對網印式單晶矽太陽能電池之光電特性影響..........9
2.3.2探討三氧化鎢與三氧化鉬堆疊順序效應對網印式單晶矽太陽能電池之光電特性影響..........9
2.3.3探討二氧化鉬與三氧化鉬不同厚度堆疊效應對網印式單晶矽太陽能電池之光電特性影響..........10
2.4探討二氧化鉬之真空熱處理效應、不同氣體對二氧化鉬之熱處理效應對網印式單晶矽太陽能電池之光電特性影響..........10
2.4.1探討二氧化鉬之真空熱處理效應對網印式單晶矽太陽能電池之光電特性影響..........10
2.4.2探討不同氣體對二氧化鉬之熱處理效應對網印式單晶矽太陽能電池之光電特性影響..........10
第三章 氧化鉬電洞選擇性傳輸層的熱處理與堆疊效應對網印式單晶矽太陽能電池之光電特性研究..........24
3.1探討蒸鍍完二氧化鉬層的抽真空效應對網印式單晶矽太陽能電池之光電特性影響..........24
3.1.1結果與討論..........24
3.1.2結論..........25
3.2探討二氧化鉬與三氧化鉬堆疊順序效應對網印式單晶矽太陽能電池之光電特性影響..........25
3.2.1結果與討論..........26
3.2.2結論..........27
3.3探討三氧化鎢與三氧化鉬堆疊順序效應對網印式單晶矽太陽能電池之光電特性影響..........27
3.3.1結果與討論..........27
3.3.2結論..........28
3.4探討探討二氧化鉬與三氧化鉬不同厚度堆疊效應對網印式單晶矽太陽能電池之光電特性影響..........28
3.4.1結果與討論..........28
3.4.2結論..........29
3.5探討二氧化鉬之真空熱處理效應對網印式單晶矽太陽能電池之光電特性影響..........29
3.5.1結果與討論..........30
3.5.2結論..........31
3.6探討不同氣體對二氧化鉬之熱處理效應對網印式單晶矽太陽能電池之光電特性影響..........31
3.6.1結果與討論..........32
3.6.2結論..........33
第四章 總結論與未來展望..........56
4.1總結論..........56
4.2未來展望..........56
參考文獻..........57
Extended Abstract..........60
作者簡歷..........62

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