臺灣博碩士論文加值系統

本論文研究探討氧化亞銅電子阻擋層應用於網印式單晶矽太陽能電池之光電特性研究，利用氧化亞銅電子阻擋特性來避免與電洞在矽背表面復合，其原理為氧化亞銅比矽具有較大的能隙，且其導帶與正型矽的導帶有較大的能階差，本論文改變參數分別為蒸鍍銅金屬與氧化亞銅顆粒所形成不同的氧化亞銅特性，並探討氧化亞銅厚度、加熱形式、氧氣流量及金屬電極等條件下所形成的氧化亞銅電子阻擋層特性，最後研究具有氧化亞銅的網印式單晶矽太陽能電池之老化特性，並使用紫外光光電子光譜儀、 UV/VIS/IR 光譜儀、穿透式電子顯微鏡和能量分散光譜儀分析氧化亞銅的材料特性。
實驗結果顯示，在氧氣流量為 15 sccm下，蒸鍍之銅金屬厚度為3 nm，其光電轉換效率為18.24 %，接著利用快速熱退火方式使氧氣與銅金屬形成氧化亞銅，由光電轉換效率得知，加熱使表面過氧化導致串聯電阻過高，因此後續製程皆不再採用加熱方式，接著探討蒸鍍源材料為氧化亞銅顆粒之影響，首先，在沒有通入氧氣的氛圍下改變蒸鍍氧化亞銅厚度，其結果顯示當氧化亞銅厚度為2 nm時，效率則上升至18.39 %，接著探討在固定厚度下改變氧氣流量並搭配不同金屬電極之影響，由結果得知，當氧氣流量為 15 sccm、金屬電極為銅電極，有最佳之光電轉換效率為18.47 %，接著改變氧化亞銅厚度以確認金屬電極不會對厚度造成影響。綜合上述實驗結果得知，在蒸鍍氧化亞銅顆粒其厚度為 2 nm、氧氣流量為 15 sccm、金屬電極為銅電極有最佳之開路電壓為 628 mV、短路電流為 35.60 mA/cm2、填充因子為82.56%、串聯電阻為1.56 Ω-cm2與光電轉換效率18.47 %之網印式單晶矽太陽能電池元件。

In this thesis, the applications of cuprous oxide electron-blocking layers (EBLs) on photovoltaic characteristics of screen-printed monocrystalline silicon solar cells (SPMSSCs) were explored. The electron-blocking properties of cuprous oxide were used to avoid recombination with holes on the silicon back surface. The principle is that cuprous oxide has a larger energy bandgap than silicon, and its conduction band is larger than the conduction band of p-type silicon. The parameters, including cuprous oxide formed by the evaporation of copper metal and cuprous oxide granules, thicknesses of cuprous oxide, heating method, oxygen flow, and metal electrode, were investigated. Finally, the degradation characteristics of SPMSSCs with cuprous oxide were investigated. The cuprous oxide properties were analyzed by UV photoelectron spectroscopy (UPS), UV/VIS-IR spectroscopy, transmission electron microscopy (TEM), energy dispersive spectrometer (EDS), respectively.
The experimental results show that the SPMSSCs with conversion efficiency (CE) of 18.24% were demonstrated by oxygen flow of 15 sccm, and the copper thickness of 3 nm. Next, the cuprous oxide was formed by rapid thermal annealing (RTA). From the CE properties, the surface resistance was increased by over-oxidation. Thus, the RTA was no longer used for subsequent processes. Furthermore, the effects of cuprous oxide granules were investigated. The results suggest that the CE was enhanced to 18.39 %t for the thickness of cuprous oxide granules at 2 nm under without oxygen ambient. Moreover, the effects of oxygen flow and metal electrodes were explored. The results indicate that the CE was enhanced to 18.47 % at an oxygen flow of 15 sccm and copper electrode. By changing the thickness of cuprous oxide, it was discussed that the metal electrode will not affect the CE. According to optimum conditions, the SPMSSCs with CE of 18.47 % , open-circuit voltage of 628 mV, short-circuit current density of 35.60 mA/cm2, fill factor of 82.56 %, series resistance of 1.56 Ω-cm2, were demonstrated by the cuprous oxide thickness of 2 nm formed by cuprous oxide granules, an oxygen flow of 15 sccm, and copper electrode.

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應用載子選擇性材料於太陽能電池之文獻回顧.....1
1.2氧化亞銅電子阻擋性材料的不同形成方式之文獻回顧.....2
1.3氧化亞銅電子阻擋性材料應用於太陽能光伏元件之文獻回顧.....3
1.4研究動機.....4
1.5論文架構.....4
第二章 實驗流程與特性量測.....5
2.1實驗製程.....5
2.1.1通過RCA標準清洗(Radio Corporation of America)步驟清除矽基板上之雜質與離子污染(RCA Clean).....5
2.1.2經由鹼性蝕刻溶液(KOH)對矽基板進行表面糙化處理(Texturing).....6
2.1.3藉由高溫擴散爐管將磷原子驅入矽表面形成射極(Diffusion).....6
2.1.4使用氫氟酸(DHF)將矽晶片周圍因磷擴散導致的磷玻璃(PSG)去除(PSG is removed by DHF).....6
2.1.5使用混合酸(HF+HNO3+H2SO4)藥液清除矽晶片周圍多餘的磷擴散(N+)並進行邊緣隔絕(Edge Isolation).....7
2.1.6在電漿增強化學氣相沉積(PECVD)技術中沉積氮化矽(SiNx)作為抗反射層於矽基板正表面(ARC deposition).....7
2.1.7在抗反射層上通過網版印刷技術網印銀膠並烤乾後作為金屬電極(Screen print Ag on front side).....7
2.1.8經由隧道爐對銀膠進行高溫燒結使其刺穿抗反射層(Firing).....7
2.1.9使用雷射切割技術將試片切割為2 × 2 cm2之試片大小(Laser cutting).....7
2.1.10懸塗兩層抗蝕刻阻擋膠(Polymer)用來保護矽正表面(Spinning coating).....7
2.1.11利用氫氟酸去除背面原生氧化層後移除抗蝕刻阻擋層(Native oxide is removed by DHF).....8
2.1.12蒸鍍氧化亞銅電子阻擋性材料作為載子傳輸層於矽背表面(Evaporated electron-blocking layer on rear side).....8
2.1.13蒸鍍金屬電極於載子選擇性傳輸層上(Evaporated metal electrode on rear side) .....8
2.2固定氧氣流量下，改變蒸鍍銅金屬顆粒厚度形成氧化銅之光電特性研究.....8
2.2.1固定氧氣流量下蒸鍍銅金屬顆粒形成氧化銅於矽背表面作為載子選擇性傳輸層(Evaporated Cu granule on rear side).....9
2.3在固定氧氛圍下蒸鍍銅顆粒後對氧化銅金屬加熱形成的氧化銅之光電特性研究.....9
2.3.1利用快速熱退火對蒸鍍完之矽晶片進行加熱處理(RTA treated).....9
2.4改變蒸鍍氧化亞銅顆粒所形成不同厚度的氧化亞銅之光電特性研究.....9
2.4.1蒸鍍氧化亞銅顆粒形成不同厚度的氧化亞銅於矽背表面作為載子選擇性傳輸層(Evaporated electron-blocking layer on rear side).....10
2.5改變不同氧氣流量下對氧化亞銅搭配不同金屬電極之光電特性研究.....10
2.5.1改變不同氧氣流量下蒸鍍氧化亞銅顆粒形成氧化亞銅於矽背表面作為載子選擇性傳輸層(Evaporated electron-blocking layer on rear side).....10
2.5.2蒸鍍不同金屬電極於載子選擇性傳輸層(Evaporated metal electrode on rear side) .....10
2.6固定氧氣流量下，改變氧化亞銅厚度搭配不同金屬電極之光電特性研究.....11
2.6.1固定氧氣流量下改變蒸鍍氧化亞銅顆粒厚度形成氧化亞銅於矽背表面作為載子選擇性傳輸層(Evaporated electron-blocking layer on rear side).....11
2.7探討具有氧化亞銅的網印式單晶矽太陽能電池之老化特性研究.....11
2.7.1探討具有氧化亞銅的網印式單晶矽太陽能電池之老化特性.....11
2.8太陽能光伏元件電性與物性量測.....12
2.8.1電流-電壓量測(I-V measurement).....12
2.8.2外部量子效率(External Quantum Efficiency, EQE)量測.....12
2.8.3穿透式電子顯微鏡(Transmission Electron Microscope, TEM)與能量色散光譜(Energy Dispersive X-ray Spectrometer, EDS)之物性量測.....12
第三章 氧化亞銅電子阻擋層應用於網印式單晶矽太陽能電池之光電特性研究.....33
3.1藉由蒸鍍銅金屬顆粒形成氧化銅之光電特性研究.....33
3.1.1固定氧氣流量下，改變蒸鍍銅金屬顆粒厚度形成氧化銅對網印式單晶矽太陽能電池的電壓電流量測分析(I-V measurement).....33
3.1.2結論.....35
3.1.3固定氧氛圍下，蒸鍍銅金屬顆粒後對氧化銅金屬加熱形成的氧化銅之網印式單晶矽太陽能電池的電壓電流量測分析(I-V measurement).....36
3.1.4結論.....37
3.2藉由蒸鍍氧化亞銅顆粒形成氧化亞銅之光電特性研究.....38
3.2.1改變蒸鍍氧化亞銅顆粒所形成不同厚度的氧化亞銅對網印式單晶矽太陽能電池的電壓電流量測分析(I-V measurement).....38
3.2.2結論.....39
3.2.3改變不同氧氣流量下對氧化亞銅搭配不同金屬電極對網印式單晶矽太陽能電池的電壓電流量測(I-V measurement)、外部量子效率(EQE)、穿透式電子顯微鏡(TEM)與能量色散光譜(EDS)之物性量測.....40
3.2.4結論.....41
3.2.5 固定氧氣流量下，改變氧化亞銅厚度搭配不同金屬電極對網印式單晶矽太陽能電池的電壓電流量測分析(I-V measurement).....42
3.2.6 結論.....43
3.2.7 探討具有氧化亞銅的網印式單晶矽太陽能電池之電壓電流量測分析(I-V measurement) .....43
3.2.8 結論.....44
第四章 總結論與未來展望.....70
4.1總結論.....70
4.2未來展望.....70
參考文獻.....71
Extended Abstract.....75
Abstract.....75
Introduction.....76
Experimental.....76
Results and Discussion.....77
Conclusions.....78
References.....78

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