臺灣博碩士論文加值系統

本論文研究探討各種金屬對具氧化鉬及氧化亞銅堆疊層之單晶矽太陽能電池光電 特性研究，由於二氧化鉬(MoO2)具有低溫製程、高功函數、寬能隙的特性、與矽接觸可 使能帶彎曲，因此具有較好的電洞選擇特性，同時氧化鉬是利用氧空缺傳輸電洞，因此 在沒有金半接面的情況下，亦可傳輸電洞，當氧化鉬作為電洞選擇性材料時，會大量使 用貴的金屬銀，故本論文嘗試研究取代銀金屬的各種金屬效應，並結合氧化鉬及氧化亞 銅(Cu2O)堆疊層進行實驗。實驗參數包含改變銀電極的厚度、改變銀鍍率、各種鎳厚度 搭配鋁堆疊電極、各種銀厚度搭配鋁堆疊電極、探討銀(Ag)、銅(Cu)及鋁(Al)電極對 MoO2/Cu2O 堆疊層效應、改變MoO2/Ag/Cu2O 堆疊結構中的銀厚度對元件轉換效率之 影響及調整堆疊於MoO2 上的各種摻雜銀之氧化亞銅對元件轉換效率之影響。材料分 析包含使用X 射線衍射(XRD)確認顆粒大小，利用熱場式電子顯微鏡(FESEM)觀測表 面型態，以及使用積分球測定反射率。 實驗結果顯示，當銀的熱蒸鍍速率為2.0 Å/s 時且厚度為100 nm 時，與5.0 Å/s 時 且厚度為500 nm 時的光電轉換效率一樣為20.22 %，在各種鎳厚度搭配鋁的實驗結果 可知，當蒸鍍4.5 nm 的鎳搭配200 nm 鋁時，光電轉換效率只有19.61 %，這是由於 Ni/Al 串聯電阻較高，於是嘗試利用銀作為中間層進行實驗，並在銀70 nm 時搭配200 nm 的鋁電極時獲得最佳光電轉換效率20.33 %。後續進行銀、銅及鋁電極對MoO2/Cu2O 堆疊層效應探討，實驗結果顯示，MoO2/Cu2O/Ag 的結構具有最高的轉換效率21.34 %， 而為了得到更好的傳輸特性，因此將銀插入二氧化鉬中間並改變厚度，在銀為0.5 nm 時得到最佳的光電轉換效率21.34 %，最後將銀與氧化亞銅進行共蒸鍍，並與氧化鉬堆 疊，實驗結果顯示當結構為MoO2/Cu2O:Ag/Cu2O 時，有最佳光電轉換效率21.38 %， 開路電壓為652 mV、短路電流密度為40.28 mA/cm2、填充因子為81.29 %及串聯電阻 為1.53 Ω-cm2。。

The effects of various metals on photovoltaic properties of monocrystalline silicon solar cells with molybdenum oxide and copper oxide stacked layer were investigated. Molybdenum dioxide(MoO2) exhibits favorable hole-selective properties due to its characteristics of lowtemperature processing, high work function, wide bandgap, and the ability to bend the band structure when in contact with silicon. Meanwhile, MoO2 utilizes oxygen vacancies to transport holes, so it can also transport holes without a metal-semiconductor junction. When MoO2 is used as the hole-selective material, it often involves extensive use of the expensive metal silver. Therefore, this paper attempts to study various metal effects as substitutes for silver metal, combined with MoO2 and cuprous oxide(Cu2O) stack layers for experimentation. The experimental parameters include varying the thickness of the silver electrode, altering the silver deposition rate, various nickel thicknesses paired with aluminum stack electrodes, various silver thicknesses paired with aluminum stack electrodes, investigating the effects of silver(Ag), copper(Cu), and aluminum(Al) electrodes on MoO2/Cu2O stack layers, assessing the influence of varying silver thickness in MoO2/Ag/Cu2O stack structures on device conversion efficiency(CE), and examining the impact of various silver-doped cuprous oxide layers stacked on MoO2 on device CE. Material analysis involves confirming particle size using X-ray diffraction(XRD) and observing surface morphology utilizing field emission scanning electron microscopy(FESEM) and using integral sphere to measure reflectance. The experimental results show that when the thermal evaporation rate of silver is 2.0 Å/s and the thickness is 100 nm, the CE is the same at 20.22 % as when it is 5.0 Å/s and the thickness is 500 nm. From the experimental results with various nickel thicknesses combined with aluminum, it is observed that when 4.5 nm of nickel is deposited with 200 nm of aluminum, the CE is only 19.61 %. This is attributed to the higher Ni/Al series resistance. Consequently, an attempt was made to utilize silver as an intermediate layer for experimentation. The optimal CE of 20.33 % was achieved when 70 nm of silver was combined with 200 nm of aluminum electrodes. Subsequent, investigations were conducted on the effects of silver, copper, and aluminum electrodes on MoO2/Cu2O stack layers. The experimental results revealed that the MoO2/Cu2O/Ag structure exhibited the highest CE of 21.34 %. In pursuit of better transmission characteristics, silver was inserted into the MoO2 layer with varying thicknesses. The optimal CE of 21.34 % was achieved when the silver thickness was 0.5 nm. Finally, silver was co-evaporated with Cu2O and stacked with MoO2. The experimental results revealed that when the structure was MoO2/Cu2O:Ag/Cu2O, the optimum CE reached 21.38 %, with an open-circuit voltage of 652 mV, a short-circuit current density of 40.28 mA/cm2, a fill factor of 81.29 %, and a series resistance of 1.53 Ω-cm2.

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
1.1二氧化鉬應用於太陽能電池之文獻回顧........1
1.2氧化亞銅應用於太陽能電池之文獻回顧........1
1.3應用於太陽能電池之金屬電極文獻回顧........2
1.4研究動機........4
1.5論文架構........5
第二章 實驗流程介紹及實驗參數........6
2.1 改變銀電極鍍率及厚度對氧化鉬電洞選擇性材料實驗之前段製程........6
2.1.1 使用RCA clean清洗機板表層平面的灰塵與自然產生的SiOx層........6
2.1.2 使用氫氧化鉀搭配去離子水和異丙醇進行表層平面糙化處理........7
2.1.3 將矽基板透過高溫爐管進行磷擴散以產生N+射極形成P-N接面........7
2.1.4 將擴散後的基板退火使晶格重組，並消除結晶的內應力........7
2.1.5 利用氫氟酸、硝酸與硫酸的混合溶液去除擴散時產生的磷玻璃與進行邊緣隔絕........8
2.1.6 利用PECVD沉積氮化矽(SiNx)在矽基板正面作為抗反射層(ARC)........8
2.1.7 在矽基板正面網印銀膠並烤乾........8
2.1.8 利用燒結爐將被網印在矽基板正面的銀電極燒破氮化矽層與基板正面的P-N接面產生接觸........8
2.1.9 利用雷射切割機切割矽基板使其達到製程需求........8
2.1.10 利用旋轉塗佈機旋塗兩層抗蝕刻聚合物於矽基板正面並烤乾........9
2.1.11 利用調配過的氫氟酸再一次清除矽基板背面的SiOx層........9
2.2 探討銀電極鍍率及厚度對氧化鉬電洞選擇性材料之效應........9
2.2.1 在試片的背面蒸鍍MoO2........9
2.2.2 在試片的背面蒸鍍銀電極........10
2.2.3 I-V曲線量測........10
2.2.4 熱場式電子顯微鏡(FE-SEM)之材料分析........10
2.2.5 X光繞射儀(XRD)之材料分析........10
2.2.6 反射用測光積分球之材料分析........11
2.3 各種鎳(Ni)厚度搭配鋁堆疊電極對MoO2電洞選擇性材料之效應........11
2.3.1 在試片的背面蒸鍍MoO2........11
2.3.2 在試片的背面蒸鍍鎳........11
2.3.3 在試片的背面蒸鍍鋁電極........12
2.3.4 I-V曲線量測........12
2.3.5 反射用測光積分球之材料分析........12
2.4 各種銀(Ag)厚度搭配鋁堆疊電極對MoO2電洞選擇性材料之效應........13
2.4.1 在試片的背面蒸鍍MoO2........13
2.4.2 在試片的背面蒸鍍銀........13
2.4.3 在試片的背面蒸鍍鋁電極........14
2.4.4 I-V曲線量測........14
2.4.5 反射用測光積分球之材料分析........14
2.5 探討銀、銅及鋁電極對MoO2/Cu2O堆疊層之效應........15
2.5.1 在試片的背面蒸鍍MoO2........15
2.5.2 在試片的背面蒸鍍Cu2O........15
2.5.3在試片的背面蒸鍍銀(Ag)、銅(Cu)及鋁(Al)電極........15
2.5.4 I-V曲線量測........16
2.5.5 反射用測光積分球之材料分析........16
2.6 改變MoO2/銀/Cu2O堆疊結構中的銀厚度對元件轉換效率之影響........16
2.6.1 在試片的背面蒸鍍MoO2........17
2.6.2 在試片的背面蒸鍍銀........17
2.6.3 在試片的背面蒸鍍Cu2O........17
2.6.4 在試片的背面蒸鍍銀電極........18
2.6.5 I-V曲線量測........18
2.7 調整堆疊於MoO2上的各種摻雜銀之氧化亞銅(Cu2O:Ag)對元件轉換效率之影響........18
2.7.1 蒸鍍MoO2於試片的背面........18
2.7.2 蒸鍍堆疊層(Stacked Layers)於試片的背面........19
2.7.3 在試片的背面蒸鍍銀電極........19
2.7.4 I-V曲線量測........20
第三章 實驗結果與討論........38
3.1 探討銀電極鍍率及厚度對MoO2電洞選擇性材料之效應........38
3.1.1 結論........39
3.2各種鎳厚度搭配鋁堆疊電極對MoO2電洞選擇性材料之效應........39
3.2.1結論........40
3.3各種銀厚度搭配鋁堆疊電極對MoO2電洞選擇性材料之效應........40
3.3.1結論........41
3.4探討銀、銅及鋁電極對MoO2/Cu2O堆疊層效應........41
3.4.1 結論........42
3.5 改變氧化鉬/銀/氧化亞銅堆疊結構中的銀厚度對元件轉換效率之影響........43
3.5.1 結論........43
3.6 調整堆疊於MoO2上的各種摻雜銀之氧化亞銅(Cu2O:Ag)對元件轉換效率之影響........44
3.6.1 結論........44
第四章 實驗結論與未來展望........73
4.1總結論........73
4.2未來展望........73
參考文獻........74
Extended abstract........77

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