本研究探討網印式與原子層沉積氧化鋁堆疊鈍化層對射極鈍化背接觸式(PERC)單晶矽太陽能電池之光電特性影響，由於網印式單晶矽太陽能電池背表面電極通常使用鋁-背表面電場(Al-BSF)，其復合速率約為200至600 cm/s，而目前商業化的射極鈍化背接觸式太陽能電池為了降低背表面電場的高復合速率及增加背表面帶負電荷的場效鈍化，多數均為沉積氧化鋁(Al2O3)搭配氮化矽(Si3N4)堆疊鈍化層，同時在PERC元件中的雷射開孔製程是複雜的，因此本實驗採用原子層化學氣相沉積之氧化鋁當鈍化層，同時搭配網印式氧化鋁膠當作阻障層，藉由氧化鋁膠相關參數包括氧化鋁膠的膠體種類、網版的乳膠厚度、網印Gap以及不同的氧化鋁膠接觸面積等，研究其最佳參數，接著探討改變原子層沉積氧化鋁鈍化層的厚度及原子層沉積氧化鋁後的處理效應，同時探討網印式與原子層沉積氧化鋁堆疊鈍化層的效應。
實驗結果顯示，當改變氧化鋁膠的膠體種類時，得知氧化鋁膠的黏稠度越高越能夠有效地當作阻障層，當改變氧化鋁膠網版的乳膠厚度從5微米變化至20微米時，得知乳膠厚度為5微米時能夠獲得最低的氧化鋁膠的厚度約10微米，當改變氧化鋁膠的網印Gap從1.1變化至1.3時，得知網印氧化鋁膠Gap為1.1可做出較薄的阻障層，在改變氧化鋁膠的不同接觸面積情況下，得知氧化鋁膠的接觸面積在30 %且經由網印鋁膠Gap為1.4以及銀膠Gap為1.6時，可獲得較佳的光電轉換效率為17.77 %，同時探討網印式與原子層沉積氧化鋁堆疊層效應，當改變原子層氧化鋁的厚度從0至9奈米時，得知最佳原子層氧化鋁的厚度為6奈米，當改變原子層沉積氧化鋁後的處理蝕刻時間從0至15秒，得知原子層沉積氧化鋁後的處理蝕刻時間為5秒，經由最佳化條件的施行可獲得其開路電壓為641 mV、短路電流為35.7 mA/cm2、串聯電阻為1.6 Ω-cm2、填充因子為80.01 %及光電轉換效率為18.0 %。

In this study, the effects of screen-printed and atomic-layer-deposition (ALD) aluminum oxide (Al2O3) stacked films on photovoltaic characteristics of passivated emitter and rear contact (PERC) silicon solar cells were investigated. In general, the backside electrode of the screen-printed monocrystalline silicon solar cells was formed by aluminum back-surface-field (Al-BSF) with recombination rate of 200 to 600 cm/s. Currently, to reduce the high recombination rate of the Al-BSF and increase the field-effect passivation with negative charge, Al2O3 and silicon nitride (Si3N4) stacked films are mostly used on the back surface in commercial PERC cells. Moreover, the laser drilling process in PERC cells is complication. Therefore, in this work, screen-printed Al2O3 paste and ALD Al2O3 layer were adopted as the passivation layer and barrier layer, respectively. The parameters of the screen-printed Al2O3 paste, including the colloidal type of Al2O3 paste, the thickness of the emulsion, the gap of the screen, and the contact fraction between Al paste and silicon substrate, were presented. Next, the various thicknesses of the ALD Al2O3 passivation layers and effects of after ALD Al2O3 were investigated. At the same time, the effects of the Al2O3 stacked films formed by screen-printed and ALD techniques on the passivation layers of the PERC cells were addressed.
The results indicated that the enhanced properties of the diffusion barrier can be demonstrated by increasing the viscosity in the Al2O3 paste when changing the colloidal types of the Al2O3 paste. When changing the thickness of the Al2O3 paste from 5 to 20 μm, it was found that the minimum thickness of the Al2O3 paste with around 10 μm was demonstrated for the thickness of the emulsion at 5 μm. When changing the gap of the screen ranged from 1.1 to 1.3, a thinner diffusion barrier layer can be achieved by a gap of 1.1. In the case of changing the different contact fraction, it was found that the better photovoltaic characteristics were presented by the contact fraction of 30 % combined with the gap of Al paste at 1.4 and the gap of the Ag paste at 1.6, a CE of 17.77 %. The photovoltaic characteristics of the PERC cells with screen-printed Al2O3 paste only can be enhanced by the combination of screen-printed and ALD deposited Al2O3 passivation layers. When changing the thickness of by ALD Al2O3 from 0 to 9 nm, it was found the thickness the best by ALD Al2O3 of 6 nm. When changing the after ALD Al2O3 of processing etched time from 0 to 15 sec, it was found the etched time the best of 5 sec. According to the optimum parameters, a CE of 18.0 % with an open-circuit voltage (Voc) of 641 mV, a short-circuit current density (Jsc) of 35.7 mA/cm2, a series resistance (Rs) of 1.6 Ω-cm2, and a fill factor (F.F.) of 80.01 % were demonstrated.

摘要..............................i
Abstract..............................ii
誌謝..............................iv
目錄..............................v
表目錄..............................viii
圖目錄..............................ix
第一章 緒論..............................1
1.1 高效率太陽能電池之發展概況..............................1
1.2 背表面射極鈍化應用於矽基太陽能電池之發展概況..............................1
1.3 研究動機..............................6
1.4 論文架構..............................6
第二章 實驗流程與特性量測..............................7
2.1本研究所使用的相關製程..............................7
2.1.1去除矽基板表面原生自然氧化層及表面微粒清洗(Radio Corporation of America Clean ; RCA Clean)..............................7
2.1.2使用氫氧化鉀(KOH)、異丙醇(IPA)以及去離子水(DIW)溶液進行鹼性濕式蝕刻形成表面金字塔粗糙化(Pyramid-Textured)..............................8
2.1.3利用高溫爐管進行磷擴散(Phosphorus Diffusion)製程在P-type基板形成射極(n+)..............................9
2.1.4使用二氧化矽蝕刻液(Buffer Oxide Etch : BOE)移除表面殘留之磷玻璃(PSG)物質..............................9
2.1.5藉由電漿輔助化學氣相沉積(Plasma Enhance Chemical-Vapor-Deposition ; PECVD)系統在前表面沉積氮化矽(Si3N4)抗反射層..............................10
2.1.6使用雷射切割機，將試片切割成2 cm x 2 cm..............................10
2.1.7使用二氧化矽蝕刻液進行濕式去除表面原生自然氧化層..............................10
2.1.8 使用熱原子層沉積(Atomic Layer Deposition ; ALD)系統在背表面沉積三氧二化鋁(Aluminum Oxide ; Al2O3)鈍化層..............................11
2.1.9使用網印氧化鋁膠進行背表面沒有圖案化或有圖案化開孔，接著將氧化鋁膠烤乾..............................11
2.1.10利用旋塗可剝膠(Polymer)當作背面抗蝕刻阻擋層，接著將聚合物膠體烤乾..............................12
2.1.11 在熱原子層沉積三氧二化鋁之後，使用二氧化矽蝕刻液對於沉積後的處理效應，接著將可剝膠(Polymer)移除..............................12
2.1.12使用背面網印整面鋁膠當作背面電極，接著將鋁膠烤乾..............................12
2.1.13使用正面網印分指狀銀膠當作正面電極，接著將銀膠烤乾..............................13
2.1.14藉由高溫燒結爐進行共燒結，使正面銀膠刺穿氮化矽(Si3N4)抗反射層與射極接觸，而背面鋁膠形成鋁-局部背表面電場(Aluminum-Local Back Surface Field ; Al-LBSF)..............................13
2.2藉由網印式氧化鋁鈍化層探討射極鈍化背接觸式太陽能電池之光電特性研究..............................14
2.2.1本研究所使用的前段製程..............................14
2.2.2探討在沒有圖案化的各種網印A12O3 Paste是否能夠阻擋PERC Al 、General Al Paste刺穿介電材料與基板接觸之光電特性研究..............................14
2.2.3在沒有圖案化的A12O3 Paste情況下，探討各種Gap是否能夠阻擋PERC Al、General Al Paste刺穿介電材料與基板接觸之光電特性研究..............................14
2.2.4在有圖案化的A12O3 Paste情況下，探討各種網印電極Gap之光電特性研究..............................14
2.2.5在有圖案化的A12O3 Paste情況下，探討各種正方形圖案化的Local Al Area之光電特性研究..............................15
2.2.6在有圖案化的A12O3 Paste情況下，探討各種矩形圖案化的Local Al Area之光電特性研究..............................15
2.2.7在有圖案化的A12O3 Paste情況下，探討各種線條圖案化的Local Al Area之光電特性研究..............................15
2.2.8在有圖案化的A12O3 Paste情況下，探討各種去除表面原生自然氧化層蝕刻時間之光電特性研究..............................15
2.3藉由網印式與原子層沉積氧化鋁堆疊鈍化層探討射極鈍化背接觸式太陽能電池之光電特性研究..............................16
2.3.1探討網印式與原子層沉積氧化鋁之光電特性研究..............................16
2.3.2探討各種ALD Al2O3厚度及沉積後的處理效應之光電特性研究..............................16
2.4 光伏元件電性分析..............................16
2.4.1 電流-電壓(I-V)量測系統..............................16
2.4.2 外部量子效率量測(External Quantum Efficiency ; EQE)系統..............................17
2.5 材料物性量測..............................17
2.5.1 正置金相顯微鏡..............................17
2.5.2 掃描式電子顯微鏡(Scanning Electron Microscope；SEM)..............................17
第三章 網印式與原子層沉積氧化鋁堆疊鈍化層對射極鈍化背接觸式單晶矽太陽能電池之光電特性影響..............................39
3.1藉由網印式氧化鋁鈍化層探討射極鈍化背接觸式單晶矽太陽能電池之光電特性研究的結果與討論..............................39
3.1.1 探討在沒有圖案化的各種網印Al2O3 Paste是否能夠阻擋PERC Al、General Al Paste刺穿介電材料與基板接觸之光電特性研究..............................39
3.1.2 在沒有圖案化的Al2O3 Paste情況下，探討各種Gap是否能夠阻擋PERC Al、General Al Paste刺穿介電材料與基板接觸之光電特性研究..............................40
3.1.3 在有圖案化的Al2O3 Paste情況下，探討各種網印電極Gap之光電特性研究..............................42
3.1.4 在有圖案化的Al2O3 Paste情況下，探討各種圖案化的Local Al Area之光電特性研究..............................43
3.1.5 在網印有圖案化的Al2O3 Paste之前，探討各種去除表面原生自然氧化層蝕刻時間之光電特性研究....................................................................45
3.2藉由網印式氧化鋁鈍化層探討射極鈍化背接觸式單晶矽太陽能電池之光電特性研究的結果..............................45
3.3藉由網印式與原子層沉積氧化鋁堆疊鈍化層探討射極鈍化背接觸式單晶矽太陽能電池之光電特性研究的結果與討論..............................46
3.3.1 探討網印式與原子層沉積氧化鋁之光電特性研究..............................46
3.3.2 探討各種ALD Al2O3厚度及沉積後的處理效應之光電特性研究..............................47
3.4藉由網印式與原子層沉積氧化鋁堆疊鈍化層探討射極鈍化背接觸式單晶矽太陽能電池之光電特性研究的結果..............................47
第四章 總結論與未來展望..............................130
4.1 總結論..............................130
4.2 未來展望..............................130
參考文獻..............................131
Extended Abstract..............................134

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