臺灣博碩士論文加值系統

本研究探討利用氫電漿處理增強具氧化鉬電洞選擇性接觸層單晶矽太陽能電池之光電特性研究。首先，為了增加氧化鉬電洞選擇性接觸層的電流傳導，藉由調整氧化鉬的蒸鍍速率，探討是否可增強光電流。接著，因為氧化鉬電洞選擇性接觸層與單晶矽接面特性不佳，為了增加其鈍化效果進一步提升太陽能元件光電轉換效率，因而提出氫電漿處理，使得矽基板與氧化鉬異質界面陷阱減少。實驗中藉由改變氫電漿的參數包含電漿處理後的清洗、電漿處理製程整合順序、電漿功率大小、電漿處理時間、不同的氫含量與各種電漿處理溫度等。
實驗結果顯示，當鍍率大於25 nm/min時則二氧化鉬中電洞傳導之電流陷逐漸減少導致光電轉換效率下降至18.10%，當二氧化鉬鍍率控制在3 nm/min時可增加光電轉換效率至18.52%，其增加率為0.42%。接著探討BOE清洗對於氫電漿處理之影響，結果顯示電漿BOE後清洗能增加元件的光電轉換效率0.14%，接續實驗氫電漿處理與網印銀電極整合順序優化，結果顯示先氫電漿處理後網印之製程順序不但能省略BOE清洗步驟並且具有較佳之光電轉換效率為18.83%增加0.31%。接續實驗優化氫電漿處理之瓦特、秒數、氣體比例與處理溫度之氫電漿參數，結果顯示氫電漿瓦特數為60瓦、處理時間為50秒、處理溫度250℃、氫氣與氬氣比例為氣體比例為100:80(Ar:H2)可得最佳光電轉換效率18.99%，提升0.47%。綜合上面實驗結果顯示當二氧化鉬蒸鍍速率3 nm/min，進行氫氣電漿預處理後網印之流程，搭配氫電漿功率為60瓦、電漿處理時間為50秒、氣體比例為100:80 (Ar:H2)、載台溫度為250℃，可得最高光電轉換效率18.99%，其開路電壓為656 mV、短路電流為36.54 mA/cm2、填充因子為78.95%、串聯電阻為1.69 Ω-cm2與界面陷阱密度1.7×1014 cm-2eυ-1之太陽能電池元件。

In this study, the enhanced photovoltaic characteristics of monocrystalline silicon solar cells with molybdenum oxide hole-selective contact layers (HCLs) by hydrogen plasma treatments (HPT) were investigated. Firstly, to enhance the current transport of molybdenum oxide HCLs, the evaporated rates of MoOx were appropriately changed for photocurrent enhancement. Then, to enhance silicon solar cell efficiency, the HPT was proposed due to poor passivation between silicon and molybdenum oxide interface. The parameters, including post-HPT cleaning, the sequence of HPT, plasma power, treated time, various hydrogen contents and treated temperature, were presented.
The results indicate that the photocurrent of MoOx decreases for above the evaporated rate of 25 nm/min. On the other hand, the photocurrent of MoOx increases for below 3 nm/min. The conversion efficiency (CE) enhancement was about 0.5% from 18.1% to 18.52%. Furthermore, the BOE post-HPT cleaning was achieved. The results show that the CE of 0.14% was addressed for BOE post-HPT cleaning. Moreover, the sequences of HPT and screen-printed silver paste were demonstrated. The results suggest that the CE of 0.31% was achieved for HPT first and screen-printed silver paste last processes. Next, the results show that the CE of 0.47% enhancement was presented for plasma power of 60 W, treated time of 50 s, treated temperature of 250 oC and the Ar/H2 ratio of 100/80. According to the optimum parameters, the device with a CE of 18.99 %, an open-circuit voltage of 656 mV, a short-circuit current density of 36.54 mA/cm2, a fill factor of 78.95%, a series resistance of 1.69 Ω-cm2, the fof 1.7 x 1014 cm-2-eV-1,were demonstrated.

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
1.1二氧化鉬載子選擇特性應用於太陽能電池之文獻回顧..........1
1.2增強二氧化鉬載子選擇特性之文獻回顧..........2
1.3電漿預處理與對氧化物薄膜後處理之文獻回顧..........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前段實驗流程..........5
2.1.1 去除基板表面不純物與自然氧化層(RCA clean)..........5
2.1.2 氫氧化鉀鹼性溶液(KOH)對晶片進行糙化處理(Texturing)..........6
2.1.3 高溫爐管對正面進行射極磷擴散(Phosphorus diffusion)..........6
2.1.4 擴散後磷玻璃去除(PSG removed)..........6
2.1.5 擴散後邊緣隔絕(edge isolation)..........6
2.1.6 電漿輔助化學氣相沉積(PECVD)正面沉積氮化矽抗反射層(ARC Deposition)..........6
2.1.7 晶片雷射切割(Laser cutting)..........6
2.2 蒸鍍速率對二氧化鉬電洞選擇性材料之光電特性研究..........7
2.2.1 網版印刷正面圖形化銀電極(Screen-Print Ag)..........7
2.2.2 燒結爐燒結正面銀電極(Firing)..........7
2.2.3 旋塗抗蝕刻阻擋膠(Spin coated polymer)..........7
2.2.4 稀釋氫氟酸去除背面氧化層(Removed oxide by DHF)..........7
2.2.5 背面蒸鍍不同鍍率之二氧化鉬電洞選擇層(Evaporation MoO2)..........8
2.2.6 背面蒸鍍銀電極(Evaporation Ag)..........8
2.3.電漿預處理與BOE清洗效應對二氧化鉬電洞選擇性材料之光電特性之研究..........8
2.3.1 網版印刷正面圖形化銀電極(Screen-Print Ag)..........8
2.3.2 燒結爐燒結正面銀電極(Firing)..........8
2.3.3 旋塗抗蝕刻阻擋膠(Spin coated polymer)..........9
2.3.4 稀釋氫氟酸去除背面氧化層(Removed oxide by DHF)..........9
2.3.5 旋塗抗蝕刻阻擋膠(Spin coated polymer)..........9
2.3.6 電漿預處理(Plasma pretreatment)..........9
2.3.7 稀釋氫氟酸去除背面氧化層(Removed oxide by DHF)..........9
2.3.8 背面蒸鍍不同鍍率之二氧化鉬電洞選擇層(Evaporation MoO2)..........9
2.3.9 背面蒸鍍銀電極(Evaporation Ag)..........10
2.4 網印與電漿預處理的順序對二氧化鉬電洞選擇性材料之光電特性之研究..........10
2.5 電漿預處理的電漿參數對二氧化鉬電洞選擇性材料之光電特性之研究..........10
2.6 太陽能電池電性量測..........10
2.6.1 氧化鉬電洞選擇性太陽能電池電壓電流量測(I-V measurement)..........10
2.6.2 氧化鉬電洞選擇性太陽能電池電壓電容量測(C-V measurement)..........11
第三章 藉由氫電漿處理增強具氧化鉬電洞選擇性接觸層單晶矽太陽能電池之光電特性研究..........27
3.1 蒸鍍速率對二氧化鉬電洞選擇性材料之光電特性研究結果與討論..........27
3.1.1 探討蒸鍍速率對二氧化鉬電洞選擇性材料之光伏元件電壓電流量測分析(I-V measurement)..........27
3.1.2 探討蒸鍍速率對二氧化鉬電洞選擇性材料之光伏元件電壓電容量測分析(C-V measurement)..........28
3.1.3 總結與討論..........28
3.2 電漿預處理及BOE清洗效應對二氧化鉬電洞選擇性材料之光電特性之研究結果與討論..........28
3.2.1 電漿預處理及BOE清洗效應對二氧化鉬電洞選擇性材料之光伏元件電壓電流量測分析(I-V measurement)..........29
3.2.2 電漿預處理及BOE清洗效應對二氧化鉬電洞選擇性材料之光伏元件電壓電容量測分析(C-V measurement)..........29
3.2.3 總結與討論..........30
3.3 網印與電漿預處理的製程順序對二氧化鉬電洞選擇性材料之光電特性之研究結果與討論..........30
3.3.1 網印與電漿預處理的製程順序對二氧化鉬電洞選擇性材料之光伏元件電壓電流量測分析(I-V measurement)..........30
3.3.2 網印與電漿預處理的製程順序對二氧化鉬電洞選擇性材料之光伏元件電壓電容量測分析(C-V measurement)..........31
3.3.3 總結與討論..........31
3.4 電漿預處理的電漿功率對於二氧化鉬電洞選擇性材料之光電特性之研究結果與討論..........31
3.4.1 電漿預處理的電漿功率對二氧化鉬電洞選擇性材料之光伏元件電壓電流量測分析(I-V measurement)..........31
3.4.2 電漿預處理的電漿功率對二氧化鉬電洞選擇性材料之光伏元件電壓電容量測分析(C-V measurement)..........32
3.4.3 總結與討論..........34
3.5 電漿預處理的氣體比例對於二氧化鉬電洞選擇性材料之光電特性之研究結果與討論..........34
3.5.1 電漿預處理的氣體比例對二氧化鉬電洞選擇性材料之光伏元件電壓電流量測分析(I-V measurement)..........35
3.5.2 電漿預處理的氣體比例對二氧化鉬電洞選擇性材料之光伏元件電壓電容量測分析(C-V measurement)..........35
3.5.3 總結與討論..........35
3.6 電漿預處理的溫度對於二氧化鉬電洞選擇性材料之光電特性之研究結果與討論..........36
3.6.1 電漿預處理的溫度對二氧化鉬電洞選擇性材料之光伏元件電壓電流量測分析(I-V measurement)..........36
3.6.2 電漿預處理的溫度對二氧化鉬電洞選擇性材料之光伏元件電壓電容量測分析(C-V measurement)..........36
3.6.3 總結與討論..........37
第四章 總結論與未來展望..........97
4.1 總結與討論..........97
4.2 未來展望..........97
參考文獻..........98
Extended Abstract..........101
Abstract..........101
Introduction..........102
Experimental..........102
References..........103

[1].Y. Hwang, C. S. Park, J. Kim, J. Kim, J. Y. Lim, H. Choi, J. Jo, and E. Lee, “Effect of laser damage etching on i-PERC solar cells,” Renew. Energy, vol. 79, no. 1, pp. 131–134, 2015.
[2].C. Osterwald, G. Cheek, J. B. Dubow, and V. R. P. Verneker, “Molybdenum trioxide (MoO3)/silicon photodiodes,” Appl. Phys. Lett., vol. 35, no. 10, pp. 775–776, 1979.
[3].J. Bullock, D. Yan, A. Cuevas, Y. Wan, and C. Samundsett, “N- and p-type silicon solar cells with molybdenum oxide hole contacts,” Energy Procedia, vol. 77, pp. 446–450, 2015.
[4].W. Yoon, J. E. Moore, E. Cho, D. Scheiman, N. A. Kotulak, E. Cleveland, Y. W. Ok, P. P. Jenkins, A. Rohatgi, and R. J. Walters, “Hole-selective molybdenum oxide as a full-area rear contact to crystalline p-type Si solar cells,” Jpn. J. Appl. Phys., vol. 56, pp. 08MB18, 2017.
[5].C. Battaglia, S. M. d. Nicolas, S. D. Wolf, X. Yin, M. Zheng, C. Ballif, and A. Javey, “Silicon heterojunction solar cell with passivated hole selective MoOx contact,” Appl. Phys. Lett., vol. 104, no. 11, pp. 113902, 2014.
[6].L. Gerling, S. Mahato, C. Voz, R. Alcubilla, and J. Puigdollers, “Characterization of transition metal oxide/silicon heterojunctions for solar cell applications,” Appl. Sci., vol. 5, no. 4, pp. 695–705, 2015.
[7].L. G. Gerling, S. Mahato, A. M. Vilches, G. Masmitja, P. Ortega, C. Voz, R. Alcubilla, and J. Puigdollers, “Transition metal oxides as hole-selective contacts in silicon heterojunctions solar cells,” Sol. Energy Mater. Sol. Cells, vol. 145, pp. 109–115, 2016.
[8].M. T. Greiner, L. Chai, M. G. Helander, W. M. Tang, and Z. H. Lu, “Metal/metal-oxide interfaces: how metal contacts affect the work function and band structure of MoO3,” Adv. Funct. Mater., vol. 23, no. 2, pp. 215–226, 2013.
[9].J. Tong, Y. Jiang, N. Song, S. Lim, O. Zi, and A. Lennon, “Hydrogen molybdenum bronzes for hole transport layers on crystalline silicon solar cells,” IEEE 44th Photovolt. Spec. Conf. PVSC, pp. 1–3, 2018.
[10].C. Tao, S. Ruan, X. Zhang, G. Xie, L. Shen, X. Kong, W. Dong, C. Liu, and W. Chena, “Performance improvement of inverted polymer solar cells with different top electrodes by introducing a MoO3 buffer layer,” Appl. Phys. Lett., vol. 93, no. 19, pp. 3–6, 2008.
 
[11].X. Haitao and Z. Xiang, “Investigation of hole injection enhancement by MoO3 buffer layer in organic light emitting diodes,” J. Appl. Phys., vol. 114, no. 24, pp. 30–34, 2013.
[12].M. T. Greiner, L. Chai, M. G. Helander, W. M. Tang, and Z. H. Lu, “Transition metal oxide work functions: the influence of cation oxidation state and oxygen vacancies,” Adv. Funct. Mater., vol. 22, no. 21, pp. 4557–4568, 2012.
[13].C. T. Lin, C. H. Yeh, M. H. Chen, S. H. Hsu, C. I. Wu, and T. W. Pi, “Influences of evaporation temperature on electronic structures and electrical properties of molybdenum oxide in organic light emitting devices,” J. Appl. Phys., vol. 107, no. 5, pp. 1–4, 2010.
[14].B. Dasgupta, W. P. Goh, Z. E. Ooi, L. M. Wong, C. Y. Jiang, Y. Ren, E. S. Tok, J. Pan, J. Zhang, and S. Y. Chiam, “Enhanced extraction rates through gap states of molybdenum oxide anode buffer,” J. Phys. Chem. C, vol. 117, no. 18, pp. 9206–9211, 2013.
[15].P. S. Wang, Y. Y. Lo, W. H. Tseng, M. H. Chen, and C. I. Wu, “Enhancing the incorporation compatibility of molybdenum oxides in organic light emitting diodes with gap state formations,” J. Appl. Phys., vol. 114, no. 6, 2013.
[16].M. Vasilopoulou, A. M. Douvas, D. G. Georgiadou, L. C. Palilis, S. Kennou, L. Sygellou, A. Soultati, I. Kostis, G. Papadimitropoulos, D. Davazoglou, and P. Argitis, “The influence of hydrogenation and oxygen vacancies on molybdenum oxides work function and gap states for application in organic optoelectronics,” J. Am. Chem. Soc., vol. 134, no. 39, pp. 16178–16187, 2012.
[17].F. K. Chang, Y. C. Huang, J. S. Jeng, and J. S. Chen, “Band offset of vanadium-doped molybdenum oxide hole transport layer in organic photovoltaics,” Solid. State. Electron., vol. 122, pp. 18–22, 2016.
[18].P. Schulz, S. R. Cowan, Z. L. Guan, A. Garcia, D. C. Olson, and A. Kahn, “NiOX/MoO3 Bi-layers as efficient hole extraction contacts in organic solar cells,” Adv. Funct. Mater., vol. 24, no. 5, pp. 701–706, 2014.
[19].W. Cao, Y. Zheng, Z. Li, E. Wrzesniewski, W. T. Hammond, and J. Xue, “Flexible organic solar cells using an oxide/metal/oxide trilayer as transparent electrode,” Org. Electron., vol. 13, no. 11, pp. 2221–2228, 2012.
[20].Y. D. Kim, S. Park, J. Song, S. J. Tark, M. G. Kang, S. Kwon, S. Yoon, and D. Kim, “Surface passivation of crystalline silicon wafer via hydrogen plasma pre-treatment for solar cells,” Sol. Energy Mater. Sol. Cells, vol. 95, no. 1, pp. 73–76, 2011.
[21].I. Martıin, M. Vetter, A. Orpella, C. Voz, J. Puigdollers, R. Alcubilla, A. V. Kharchenko, and P. Cabarrocas, “Improvement of crystalline silicon surface passivation by hydrogen plasma treatment,” Appl. Phys. Lett, vol. 1474, no. 2004, pp. 15–18, 2013.
 
[22].S. J. Lee, S. H. Kim, D.W. Kim, K. H. Kim, B. K. Kim, and J. Jang, “Effect of hydrogen plasma passivation on performance of HIT solar cells,” Sol. Energy Mater. Sol. Cells, vol. 95, no. 1, pp. 81–83, 2011.
[23].T. Hsu, B. Anthony, R. Qian, J. Irby, S. K Banerjee, A. Tasch, S. Lin, H. Marcus, and C. Magee, “Cleaning and passivation of the Si (100) surface by low temperature remote hydrogen plasma treatment for Si epitaxy,” J. Electron. Mater., vol. 20, no. 3, pp. 279–287, 1991.
[24].J. W. Lin, C. H. Wu, S. W. Wu, W. P. Hseih, C. H. Du, and T. S. Chao, “Enhancement of open-circuit voltage using CF4 plasma treatment on nitric acid oxides,” IEEE Electron Device Lett., vol. 34, no. 5, pp. 665–667, 2013.
[25].T. Suni, K. Henttinen, I. Suni, and J. Makinen, “Effects of plasma activation on hydrophilic bonding of Si and SiO,” J. Electrochem. Soc., vol. 149, no. 6, p. G348, 2002.
[26].P. S. Wang, I. W. Wu, W. H. Tseng, M. H. Chen, and C. I. Wu, “Enhancement of current injection in organic light emitting diodes with sputter treated molybdenum oxides as hole injection layers,” Appl. Phys. Lett., vol. 98, no. 17, pp. 7–9, 2011.
[27].Y. Kim, B. J. Yoo, R. Vittal, Y. Lee, N. G. Park, and K. J. Kim, “Low-temperature oxygen plasma treatment of TiO2 film for enhanced performance of dye-sensitized solar cells,” J. Power Sources, vol. 175, no. 2, pp. 914–919, 2008.
[28].P. Cao, D. X. Zhao, J. Y. Zhang, D. Z. Shen, Y. M. Lu, B. Yao, B. H. Li, Y. Bai, and X. W. Fan., “Optical and electrical properties of p-type ZnO fabricated by NH3 plasma post-treated ZnO thin films,” Appl. Surf. Sci., vol. 254, no. 9, pp. 2900–2904, 2008.
[29].P. F. Cai, J. B. You, X. W. Zhang, J. J. Dong, X. L. Yang, Z. G. Yin, and N. F. Chen., “Enhancement of conductivity and transmittance of ZnO films by post hydrogen plasma treatment,” J. Appl. Phys., vol. 105, no. 8, 2009.
[30].C. Wang, J. R. Chen, and R. Li, “Studies on surface modification of poly (tetrafluoroethylene) film by remote and direct Ar plasma,” Appl. Surf. Sci., vol. 254, no. 9, pp. 2882–2888, 2008.
[31].D. Ahiboz, H. Nasser, and R. Turan, “Admittance analysis of thermally evaporated-hole selective MoO3 on crystalline silicon,” Proc. Int. Renew. Sustain. Energy Conf. IRSEC, pp. 144–151, 2017.