本研究論文探討藉由鹼化學處理之矽表面微結構對具氧化鉬電洞選擇性接觸層之單晶矽太陽能電池光電特性研究 ，由於氧化鉬與矽表面之間的附著力不佳，因此需增強矽表面微結構特性，第一種實驗主要使用氨水及去離子水的混合溶液來改變矽表面的結構，其參數包含不同氨水濃度、處理時間、與氫氟酸的浸泡組合及溫度等，藉此提升氧化鉬與矽表面的附著力。接續，第二種實驗主要使用氨水、雙氧水及去離子水的混合溶液對矽表面做處理，透過不同的氨水濃度及處理時間，改變矽表面的粗糙度。經過兩種實驗的化學處理後，接著用熱蒸鍍進行氧化鉬電洞選擇性接觸層及銀金屬電極的沉積，最後使用原子力顯微鏡及掃描式電子顯微鏡分析矽表面的結構。
實驗結果顯示，第一種化學處理在氨水溶液比例NH4OH : DIW為 1 : 3搭配處理時間0.5分鐘及溶液溫度為80 oC的情況下，其最佳光電轉換效率為21.37 %，與未進行化學處理的元件可提升0.67 %，開路電壓為652 mV、短路電流39.6 mA/cm2、填充因子82.6 %及串聯電阻1.50 Ω-cm2。接續實驗為在氨水溶液中加入雙氧水，其溶液比例為NH4OH : H2O2 : DIW = 1 : 1 : 4並搭配浸泡時間為 2 min及溶液溫度為80 oC的情況下，其最佳光電轉換效率為21.64 %，與未進行化學處理的元件可提升0.94 %，開路電壓為657 mV、短路電流39.9 mA/cm2、填充因子82.6 %及串聯電阻1.47 Ω-cm2。同時由實驗結果得知，適當的改變含有雙氧水的氨水溶液，可增加矽表面的粗糙度，有助於提高氧化鉬與矽表面的附著力，但不影響氧化鉬與矽表面的界面陷阱電荷。

In this study, photovoltaic characteristics of monocrystalline silicon solar cells (MSSCs) with molybdenum oxide hole-selective contact layers were investigated by alkali treated silicon surface microstructure. Since there is a poor adhesion between the molybdenum oxide and the silicon surface, the silicon surface microstructure was improved. Thus, in this study, silicon surfaces were presented by various chemical solutions. Firstly, the silicon surfaces were modified by the mixed ammonium hydroxide (NH4OH) and deionized water (DIW). The experimental parameters, including various concentrations, treated time, immersion combination with hydrofluoric acid (HF) and temperature, were proposed to improve the adhesion of molybdenum oxide and silicon surface. Next, the treatment of silicon surface was modified by the mixed NH4OH, H2O2 and DIW. The roughness of silicon surface was enhanced by various solution concentrations and treated time. After two kinds of chemical surface treatments, MoOx hole-selective contact layers and silver metal were deposited by the thermal evaporation process. Finally, the surface structure was analyzed by atomic force microscope (AFM) and scanning electron microscope (SEM).
The experimental results show that photovoltaic conversion efficiency (CE) with 0.67% improvement can be demonstrated by the mixed NH4OH and DIW solution in the ratio of 1:3 (volume) for 0.5 min, and the solution temperature of 80 oC. The treated devices with an open-circuit voltage of 652 mV, a short-circuit current density of 39.6 mA/cm2, a fill factor of 82.6 %, a series resistance of 1.50 Ω-cm2, and the CE of 21.37 % were demonstrated. To investigate the effects of NH4OH concentration containing H2O2, various NH4OH concentrations and treated time were investigated. Compared with the MSSCs without NH4OH/H2O2/DIW treatment, the CE was improved by approximately 0.94 %. The results suggest that the MSSCs with the CE of 21.64 %, an open-circuit voltage of 657 mV, a short-circuit current density of 39.9 mA/cm2, a fill factor of 82.6 %, and a series resistance of 1.47 Ω-cm2, were addressed at the mixed NH4OH, H2O2, and DIW solution in the ratio of 1:1:4 (volume) for 2 min, and 80 oC. The experimental results indicate that the roughness of the silicon surface can be enhanced by turning the ratio of NH4OH and H2O2. Moreover, the interface trap density was not degraded.

摘要.....i
Abstract.....ii
誌謝.....iii
目錄.....iv
表目錄.....vi
圖目錄.....vii
第一章 緒論.....1
1.1鈍化效果對太陽能光伏元件的影響之文獻回顧.....1
1.2 氧化鉬及載子選擇性材料應用於太陽能電池之文獻回顧.....1
1.3矽基板對表面微結構樣貌應用於薄膜之文獻回顧.....2
1.4研究動機.....4
1.5論文架構.....5
第二章 實驗流程與特性測量.....6
2.1實驗製程.....6
2.1.1通過RCA Clean(Radio Corporation of America)去除矽基板上的雜質.....6
2.1.2用鹼性蝕刻溶液(KOH)進行矽表面的糙化處理(Textured).....7
2.1.3利用高溫爐管對矽基板進行磷擴散(Diffusion)並形成n+射極層.....7
2.1.4透過酸性混合溶液去除磷玻璃(PSG)與邊緣隔絕(Edge isolation).....7
2.1.5運用電漿增強化學氣相沉積(Plasma Enhanced Chemical Vapor Deposition ; PECVD)技術沉積抗反射層(Anti-Reflection Layer ; ARL).....7
2.1.6於抗反射層上網版印刷(Screen print)銀膠並用加熱盤將其烤乾.....8
2.1.7藉由燒結爐使銀膠刺穿氮化矽(SiNx)形成載子傳輸通道.....8
2.1.8使用雷射機將矽晶片切割成20 × 20 mm2大小的試片(Laser cutting).....8
2.1.9使用旋轉塗佈機在試片正面旋塗抗蝕刻膠並將其烤乾(Spin coating).....8
2.1.10藉由氫氟酸(HF)蝕刻矽背表面的自然氧化層.....9
2.1.11改變氨水(AM)濃度及處理時間在矽背表面進行化學處理.....9
2.1.12使用氫氟酸(HF)去除矽背表面的自然氧化層並移除抗蝕刻膠.....9
2.1.13使用掃描式顯微鏡(SEM)及原子力顯微鏡(AFM)分析表面粗糙度.....9
2.1.14採用熱蒸鍍(Thermal Evaporation)技術沉積金屬氧化物於矽背表面.....9
2.1.15採用熱蒸鍍(Thermal Evaporation)技術沉積金屬於金屬氧化物上.....10
2.1.16太陽能電池元件之電流-電壓曲線(I-V curve)測量.....10
2.2研究自然氧化層、氨水(AM)濃度及處理時間對元件之影響.....10
2.3探討DHF及AM浸泡處理組合對元件之影響.....10
2.4探討AM溶液溫度對元件之影響.....10
2.5探討APM溶液濃度及處理時間對元件之影響.....11
2.6探討DHF及APM浸泡處理組合對元件之影響.....11
2.7探討APM的浸泡時間對界面陷阱密度之影響.....11
第三章 藉由鹼化學處理之矽表面微結構對具氧化鉬電洞選擇性接觸層之單晶矽太陽能電池光電特性研究.....39
3.1探討氨水(AM)濃度及處理時間對元件之光電及物理特性影響.....39
3.1.1探討氨水(AM)濃度及處理時間對元件影響之電流-電壓測量分析.....39
3.1.2探討氨水(AM)濃度及處理時間對表面結構分析.....40
3.1.3總結與討論.....41
3.2探討自然氧化層、氨水(AM)濃度及處理時間對元件之光電及物理特性影響.....41
3.2.1自然氧化層、氨水(AM)濃度及處理時間對元件影響之電流-電壓測量分析.....41
3.2.2探討自然氧化層、氨水(AM)濃度及處理時間對表面結構分析.....42
3.2.3總結與討論.....42
3.3探討DHF及AM浸泡處理組合對元件之光電特性影響.....43
3.3.1探討DHF及AM浸泡處理組合對元件影響之電流-電壓測量分析.....43
3.3.2總結與討論.....44
3.4探討AM溶液溫度對元件之光電特性影響.....44
3.4.1探討AM溶液溫度對元件影響之電流-電壓測量分析.....44
3.4.2總結與討論.....45
3.5探討APM溶液濃度及處理時間對元件之光電及物理特性影響.....45
3.5.1探討APM溶液濃度及處理時間對元件影響之電流-電壓測量分析.....45
3.5.2探討APM溶液濃度及處理時間對表面結構分析.....46
3.5.3總結與討論.....47
3.6探討DHF及APM浸泡處理組合對元件之光電特性影響.....47
3.6.1探討DHF及APM浸泡處理組合對元件影響之電流-電壓測量分析.....47
3.6.2探討DHF及APM浸泡處理組合對元件之外部量子效率測量分析.....47
3.6.3二氧化鉬與矽接面附著力之拉力測試.....48
3.6.4總結與討論.....48
3.7探討改變APM的浸泡時間對界面陷阱密度之影響.....48
3.7.1探討改變APM的浸泡時間對界面陷阱密度之電容-電壓測量分析.....48
3.7.2總結與討論.....48
第四章 總結論與未來展望.....76
4.1總結論.....76
4.2未來展望.....76
參考文獻.....77
Extended Abstract.....80

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