氮化物光伏元件之製程優化及硒化鎘量子點的應用

Process optimization for nitride-based solar cells and the application of CdSe quantum-dot down-shifting layers

黃禮智(Li-chih Huang)

指導教授 ： 賴昆佑

國立中央大學/理學院/光電科學與工程學系/碩士(2013年)

摘要

本論文主要研究內容為優化鎳金合金氧化物薄膜(oxidized-Ni/Au thin films)和電極圖案以改善氮化物太陽能電池之轉換效率。利用不同厚度之Ni/Au鍍至玻璃基板並進行不同溫度之熱退火，探討其穿透率與導電性。最後，將最佳化之Ni/Au參數配合不同之電極圖案製作於氮化物太陽能電池，並進行直流量測、分析與討論。
我們將圓形電極圖案和Ni/Au透明導電膜(5/5 nm，500℃)製作於元件上並在AM1.5標準光源下，量測其開路電壓(VOC)為2.24 V，短路電流密度(JSC)為0.273 mA/cm2，填充因子為61.2 %和轉換效率為0.373 %。實驗結果顯示，進行電極圖案和Ni/Au透明導電膜之優化可改善太陽能電池之轉換效率。
另外，本論文驗證出利用硒化鎘量子點(CdSe quantum dots)可增加異質接面(heterojunction with intrinsic thin layer, HIT)矽晶太陽能電池之轉換效率。利用化學溶膠法(chemical colloidal method)製備CdSe量子點塗佈於元件之表面用以進行發光下轉移(luminescent down-shifting)改善元件表現。在AM1.5標準光源照射下，相較於無量子點塗佈之元件，量子點濃度為0.95 wt%之元件在轉換效率有高達20%的提升。

關鍵字

氮化物 ； 太陽能電池 ； 發光下轉移 ； 硒化鎘

並列摘要

This study focuses on improve the power conversion efficiency of nitride-based solar cells by optimizing the oxidized-Ni/Au thin films and the electrode pattern. We used different Ni/Au thickness(3/3, 5/5, 4/8, 6/8, and 4/6 nm) deposited on glass substrates and annealing at different temperatures(450, 500, 550, and 600 ℃). The film’s transparency and conductivity were analyzed. The nitride-based solar cells was fabricated with the optimized parameters of Ni/Au and the electrode pattern.
The fabricated solar cell with circular electrode pattern and transparent conductive layer of Ni/Au (5/5 nm) annealed at 500℃ in air exhibits an open circuit voltage (VOC) of 2.24 V, the short-circuit current density (JSC) of 0.273 mA/cm2, the fill factor (FF) of 61.2%, and the conversion efficiency (η) of 0.373% under AM1.5 illumination. It was observed that the conversion efficiency can be improved by optimizing the electrode pattern and oxidized-Ni/Au thin films.
Furthermore, the enhanced efficiency of the heterojunction with intrinsic thin layer (HIT) silicon solar cell by CdSe quantum dots (QDs) was demonstrated. The CdSe QDs was fabricated by chemical colloidal method and employed as luminescent down-shifting (LDS) layer on the surface of a HIT Si solar cell to improve its performance. Under AM1.5 illumination, the conversion efficiency of HIT Si solar cell with CdSe QDs (0.95wt%) is improved maximally 20% as compared to the one without CdSe QDs.

並列關鍵字

nitride-based ； solar cells ； down-shifting ； CdSe

參考文獻

[23] 陳信助、林建中、王珣彣、蔡閔安、韓皓惟、蔡育霖、余沛慈和郭浩中，「增加單晶矽奈米柱太陽能電池轉換效率經由硫化鎘量子點」，國家奈米元件實驗室奈米通訊，第18卷第2期，20-25頁，2011年6月。

[24] 陳信助、林建中、蔡育霖、韓皓惟、余沛慈和郭浩中，「利用硫化鎘量子點製作高效率敏化的砷化鎵太陽能電池」，國家奈米元件實驗室奈米通訊，第19卷第2期，19-23頁，2012年6月。

[1] 楊智喬，「三五族太陽能電池製作」，國立成功大學，碩士論文，民國九十六年七月

[2] Omkar Jani, Ian Ferguson, Christiana Honsberg, and Sarah Kurtz, ”Design and characterization of GaN/InGaN solar cells”, Appl. Phys. Lett. Vol 91, pp.132117, July 2007.

[3] Jae-Phil Shim, Seong-Ran Jeon, Yon-Kil Jeong, and Dong-Seon Lee, “Improved Efficiency by Using Transparent Contact Layers in InGaN-Based p-i-n Solar Cells”, IEEE Elec. Dev. Lett. Vol 31, pp.1140-1142, October 2010.