臺灣博碩士論文加值系統

本研究探討各種矽表面形貌對具二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，為了改善氧化鉬與單晶矽基板表面之接觸特性，首先使用氫氟酸、硝酸
及去離子水的混和溶液改變單晶矽表面的粗糙度，藉由改變蝕刻時間並搭配蒸鍍不同厚
度的氧化鉬，同時改變混和溶液中的氫氟酸的濃度，探討蝕刻溶液在矽基板表面上產生
的各種粗糙度對太陽能電池光電特性的影響。接著，使用氫氟酸、硝酸及醋酸的混和溶
液，並改變溶液中氫氟酸的濃度及蝕刻時間，探討去離子水及醋酸的混合溶液對單晶矽
太陽能電池的光電特性影響，最後使用掃描式電子顯微鏡及原子力顯微鏡分析表面形
貌。
實驗結果顯示，以蝕刻溶液比例 HF：HNO3：DIW 為 40：135：25、蝕刻時間為
15 秒、蒸鍍 MoO2 厚度為 4.5 nm 時，其最佳的光電轉換效率為 20.71%，開路電壓為 0.657
V，短路電流為 39.27 mA/cm2，及填充因子為 80.24%，比起未處理的矽基板所製造的元
件可提升 0.44%。接下來的實驗為改變氫氟酸的濃度及蝕刻時間，其實驗結果顯示，蝕
刻溶液比例在 HF：HNO3：DIW 為 18：135：25 的情況下，且其蝕刻時間為 45 秒，其
光電轉換效率為 20.92%，開路電壓為 0.661 V，短路電流為 39.8 mA/cm2，填充因子為
79.31%，串聯電阻為 1.74 Ω-cm2 與粗糙度為 118 nm。最後將蝕刻溶液成分改為 HF、HNO3
及 CH3COOH 的混合溶液，其光電轉換效率沒有優於 HF、HNO3 及 DIW 的混合溶液。

In this study, the effects of various silicon surface morphologies on photovoltaic
characteristics of monocrystalline silicon solar cells (MSSCs) with molybdenum oxide
hole-selective contact (HSC) layers were investigated. First, to enhance the characteristics of
the silicon and molybdenum oxide interface, the roughness of silicon surface was modified by
the mixed hydrofluoric acid (HF), nitric acid (HNO3) and deionized water (DIW). The
parameters, including the etching time, thickness of the molybdenum oxide, as well as HF
concentration in the mixed HF/HNO3/DIW solutions were investigated. Next, the effects of
the HF concentration and etching time of the mixed HF/HNO3/CH3COOH solutions on
photovoltaic properties of the MSSCs with molybdenum oxide HSC layers were achieved.
Finally, the surface morphologies were analyzed by scanning electron microscope (SEM) and
atomic force microscope (AFM).
The experimental results indicate that the MSSCs with conversion efficiency (CE) of
20.71%, open-circuit voltage of 0.657 V, short-circuit current of 39.27 mA/cm2
, and fill factor
of 80.24%, were demonstrated by the mixed HF:HNO3:DIW solution in the ratio of 40:135:25
(volume), the etching time of 25 s, and the thickness of MoO2 with 4.5 nm. Compared with
the MSSCs without HF/HNO3/DIW treatment, the CE was enhanced by approximately 0.44%.
To investigate the effects of the HF concentration and etching time, various HF
concentrations and etching time were presented. The results suggest that the MSSCs with CE
of 20.92%, open-circuit voltage of 0.661 V, short-circuit current of 39.8 mA/cm2
, and fill
factor of 79.31%, series resistance of 1.74 Ω-cm2
, and roughness of 118 nm, were
demonstrated by the mixed HF:HNO3:DIW solution in the ratio of 18:135:25 (volume), the
etching time of 45 s. The photovoltaic properties for HF/HNO3/DIW treatment is better than
the of HF/HNO3/CH3COOH treatment ones.

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 鈍化射極背面接觸太陽能電池文獻回顧 ..... 1
1.2 二氧化鉬電洞選擇性材料應用於太陽能電池之文獻回顧 ..... 1
1.3 矽基板表面形貌對太陽能電池的影響之文獻回顧 ..... 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 使用 RCA(Radio Corporation of America) Clean 清洗矽基板表面，去除表面雜質
及微粒 ..... 5
2.1.2 使用鹼性蝕刻溶液對矽基板表面進行糙化 ..... 6
2.1.3 使用水平式高溫爐管對矽晶片進行磷擴散 ..... 6
2.1.4 浸泡氫氟酸去除磷玻璃(PSG)後邊緣絕緣 ..... 6
2.1.5 使用電漿增強型化學氣相沉積系統(Plasma Enhance Chemical Vapor Deposition；
PECVD)在矽晶片正面沉積氮化矽抗反射層(ARC) ..... 6
2.1.6 使用網印機在氮化矽(Si3N4)上網印銀(Ag)膠，並在加熱盤上烤乾 ..... 7
2.1.7 藉由燒結爐燒結矽晶片正面銀膠 ..... 7
2.1.8 使用雷射切割機將矽基板切成邊長 3 cm 的正方形試片 ..... 7
2.1.9 藉由旋轉塗佈機在矽基板正面旋塗抗蝕刻阻擋膠，並在加熱盤上烤乾 ..... 7
2.1.10 將矽基板浸泡在蝕刻溶液中，改變試片背面的表面形貌 .................................. 8
2.1.11 使用氫氟酸(DHF)去除矽基板背面原生氧化層並移除抗蝕刻阻擋膠 ..... 8
2.1.12 使用雷射切割機將矽基板切成邊長 2 cm 的正方形試片 ..... 8
2.1.13 矽基板背面蒸鍍不同厚度之二氧化鉬(MoO2)做為電洞傳輸層 ..... 8
2.1.14 矽基板背面熱蒸鍍銀(Ag)電極 ..... 9
2.1.15 太陽能電池成品光電特性量測(I-V measurement) ..... 9
2.2 探討固氧化鉬厚度，改變氫氟酸、硝酸和去離子水混和之蝕刻溶液濃度及蝕刻時間，觀察對光電轉換效率之影響 ..... 9
2.3 探討固定氧化二鉬厚度，改變氫氟酸、硝酸和去離子水混和之蝕刻溶液的濃度及蝕刻時間對表面粗糙度之影響 ..... 9
2.4 探討固氧化鉬厚度，改變氫氟酸、硝酸和醋酸混和之蝕刻溶液的濃度及蝕刻時間，並觀察其對光電轉換效率之影響 ..... 10
2.5 探討固定氧化二鉬厚度，改變氫氟酸、硝酸和去醋酸混和之蝕刻溶液的濃度及蝕刻時間對表面粗糙度之影響 ..... 10
第三章 矽表面形貌對具二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 .... 28
3.1 探討改變蝕刻時間搭配不同二氧化鉬(MoO2)厚度對太陽能電池光電特性之影響結果與討論 ..... 28
3.1.1 探討改變蝕刻時間搭配不同二氧化鉬(MoO2)厚度對太陽能電池光電特性之電壓電流量測分析(I-V measurement) ..... 28
3.1.2 總結與討論 ..... 29
3.2 探討改變氫氟酸、硝酸和去離子水混和之蝕刻溶液的濃度及蝕刻時間對太陽能電池光電特性之影響 ..... 30
3.2.1 改變氫氟酸、硝酸和去離子水混和之蝕刻溶液的濃度及蝕刻時間對太陽能電池光電特性之電壓電流量測分析(I-V measurement) ..... 30
3.2.2 改變氫氟酸、硝酸和去離子水混和之蝕刻溶液的濃度及蝕刻時間對太陽能電池光電特性之外部量子效率分析(EQE measurement) ..... 32
3.2.3 總結與討論 ..... 32
3.3 探討改變氫氟酸、硝酸和去離子水混和之蝕刻溶液的濃度及蝕刻時間對矽基板表面粗糙度之影響 ..... 33
3.3.1 改變氫氟酸、硝酸和去離子水混和之蝕刻溶液的濃度及蝕刻時間對矽基板表面粗糙度之掃描式電子顯微鏡(SEM)分析結果 ..... 33
3.3.2 改變氫氟酸、硝酸和去離子水混和之蝕刻溶液的濃度及蝕刻時間對矽基板表面粗糙度之影響的原子力顯微鏡(AFM)分析結果 ..... 33
3.3.3 總結與討論 ..... 34
3.4 探討改變氫氟酸、硝酸和醋酸混和之蝕刻溶液的濃度及蝕刻時間對太陽能電池光電特性之影響 ..... 34
3.4.1 改變氫氟酸、硝酸和醋酸混和之蝕刻溶液的濃度及蝕刻時間對太陽能電池光電特性之電壓電流量測分析(I-V measurement) ..... 34
3.4.2 改變氫氟酸、硝酸和醋酸混和之蝕刻溶液的濃度及蝕刻時間對太陽能電池光電特性之外部量子效率分析(EQE measurement) ..... 36
3.4.3 總結與討論 ..... 36
3.5 探討改變氫氟酸、硝酸和醋酸混和之蝕刻溶液的濃度及蝕刻時間對矽基板表面粗糙度之影響 ..... 37
3.5.1 改變氫氟酸、硝酸和醋酸混和之蝕刻溶液的濃度及蝕刻時間對矽基板表面粗糙度之掃描式電子顯微鏡(SEM)分析結果 ..... 37
3.5.2 改變氫氟酸、硝酸和醋酸混和之蝕刻溶液的濃度及蝕刻時間對矽基板表面粗糙度之影響的原子力顯微鏡(AFM)分析結果 ..... 37
3.5.3 總結與討論 ..... 37
第四章 總結論與未來展望 ..... 62
4.1 總結論 ..... 62
4.2 未來展望 ..... 62
參考文獻 ..... 63
Extended Abstract ..... 67

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