異質接面矽晶太陽能電池於室內外光發電應用

Application of Heterojunction with Intrinsic Thin-layer Solar Cells in Outdoor and Indoor Light-electricity

蔡佳諺(Chia-Yen Tsai)

指導教授 ： 謝嘉民

國立交通大學/電機學院/光電工程系所/碩士(2018年)

摘要

異質接面矽晶太陽能電池(HIT)具有低溫製程(<200度C)、在高溫環境下如中午時有較佳的溫度係數(-0.25%/度C)使其有較穩定的表現以及結構簡單等優點，此外HIT太陽能電池的轉換波段在350nm-1100nm與可見光頻率分布相同，因此非常適合放在室外光(AM1.5G)下作為能量來源節點以及作為室內(600lux)物聯網各式元件的能量來源。
首先，本實驗針對HIT的氧化銦錫(ITO)透明導電薄膜層進行優化。由於氧化銦鎢材料(IWO)能增加長波長(900nm-1100nm)的轉換效率(光吸收增加約2%)，因此我們與業界合作IWO透明導電薄膜層相關實驗並且將此種材料應用在HIT元件上。其中，我們使用極薄ITO(10nm) (φ~4.5eV)做為緩衝層解決IWO (φ~4.2eV)功函數較低的問題，製作成雙層透明導電薄膜結構，使效率從19.4%增加到20%。最後藉由減少網印線寬(130um->70um)並在250度C環境下放置60分鐘做退火處理，讓我們能夠穩定的製作出在室外光具有21.5%、室內光達到22uW/cm2的高效率太陽能電池。因此，HIT太陽能電池作為室外/室內能量採集，對於未來物聯網晶片自供電技術，具有相當高的潛力。

關鍵字

透明導電薄膜 ； 異質接面矽晶太陽能電池 ； 室內光 ； 能源收集

並列摘要

Heterostructure with intrinsic thin layer (HIT) solar cell is favorable for the energy-harvesting from outdoor- (1-Sun) and indoor-light (600lux) sources due to its low process temperature(<200C), high resistance to high temperature (-0.25%/C), and light absorption spectrum coincided with visible light spectrum in the range of 350-1100nm. This thesis will discuss the optimization of transparent conductive oxide (TCO), such as tin-doped indium oxide (ITO) and tungsten-doped indium oxide (IWO). First, IWO was employed to increase the light absorption in the long wavelength regime of 900-1000nm by increasing the light absorption of 2%. Moreover, the ultrathin ITO (φ~4.5eV) was used as a buffer layer to alleviate the bandgap discontinuity, so the double-layer TCO further increases HIT cell efficiency from 19.4% to 20%. Finally, the decrease in finger width of Ag electrode from 130 to 70 mm, followed by 250C annealing for 60 minutes enables further increase in cell efficiency up to 21.5% at 1-sun illumination and the output power about 22uW/cm2 at 600lux illumination. As a result, HIT solar cell used as energy harvesting in outdoor/indoor environment envisions high potential in the self-powered IoT chip in the future.

並列關鍵字

Transparent conducting oxide ； Heterojunction silicon crystalline solar cell(HJSCSC) ； Indoor light ； Energy harvesting

參考文獻

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