- 學位論文
銅鎵硒薄膜太陽能電池材料之製備與特性分析
Preparation and Characterization of Copper Gallium Diselenide Used as the Absorber in thin-film Solar Cells
摘要
本研究成功的經由溶膠凝膠法與硒化步驟製備出銅鎵硒(CuGaSe2)化合物。因為聚合作用減少金屬氧化物之間的分隔，所以溶膠凝膠法可以減少所需的反應溫度到400OC。為了補足在硒化過程中散失的鎵元素，在溶膠凝膠法中添加過量的鎵離子可得到單相CuGaSe2粉體。隨著鎵離子對銅離子的莫爾比例減少，可使CuGaSe2粉體變大。在本研究中，探討了不同硒化條件下所得到產物之組成，並利用Rietveld分析知道所得CuGaSe2為黃銅礦結構。 本研究第二部粉使用溶膠凝膠法所得之前驅物製備CuGaSe2薄膜。經由控制在溶膠凝膠法步驟中鎵離子與銅離子間的比例，可改變所得膜之表面型態與半導體特性，隨著鎵離子對銅離子比例的增加，薄膜表面的島狀銅硒化合物和載子濃度也隨著減少，但薄膜的線電阻(Ω–cm)卻會增加。可以藉由提高反應溫度或著拉長反應時間來減少雜相Cu2Se的生成。在研究中發現，CuGaSe2薄膜其生長機制為先生成中間產物的二元銅硒化合物，接著銅硒化合物在反應生成CuGaSe2.
並列摘要
Copper gallium diselenide (CuGaSe2) powders were synthesized via the sol-gel method followed by a selenization process. The sol-gel process can effectively reduce the required synthesis temperature to 400oC due to enhanced reactivity and improved composition homogeneity. The amount of the impurity phase Cu2Se was decreased when sufficient Ga3+ was added during the reactions. CuGaSe2 powders were successfully prepared when the Ga3+/Cu2+ molar ratio was increased to 2. The formation of CuGaSe2 with a pure chalcopyrite structure was confirmed via Rietveld refinement results. With decreasing the Ga3+/Cu2+ molar ratios, the particle size of the prepared CuGaSe2 powders was significant enlarged because of the copper selenide phases act as the flux for the particle growth. The optical absorption spectra reveal that the band gap of obtained CuGaSe2 is 1.68 eV. The sol-gel method combine with the selenization process was demonstrated to provide a potential approach to fabricate CuGaSe2 materials. A simple process for preparing CuGaSe2 (CGS) absorber layers was developed in this study. The sol-gel derived CGS precursor pastes were coated via a doctor blade technique followed by the selenization process. On selenization at 450oC single-phased CGS thin-films were obtained. The Raman analysis confirmed that the obtained CuGaSe2 thin films belonged to chalcopyrite structure. The amounts of Cu2Se particles on the surface of the film were reduced when the Ga3+/Cu2+ molar ratio was increased. The uniform film was obtained at the Ga3+/Cu2+ molar ratio of 1.5. The GIXD analysis reveals that the CuGaSe2 phase distributes through the whole film. Because the existence of the highly conductive Cu2Se, the resistivity of obtained CuGaSe2 films were raised with increasing the molar ratio of Ga3+ to Ga2+. The formation mechanism of CuGaSe2 thin films is proposed. The copper selenide phases formed at first and then these phases lead the formation reaction of CuGaSe2.
參考文獻
延伸閱讀
- Chen, F. S. (2012). 硒化銅銦鎵薄膜太陽電池之光吸收層薄膜製備及特性分析 [doctoral dissertation, National Taiwan University]. Airiti Library. https://doi.org/10.6342/NTU.2012.10122
- Wu, C. H. (2011). 硒化銅銦鎵薄膜太陽電池之光吸收層粉體與薄膜製備及特性分析 [doctoral dissertation, National Taiwan University]. Airiti Library. https://doi.org/10.6342/NTU.2011.10286
- 施文傑、吳彥輝（2011）。銅銦鎵硒薄膜太陽能電池光電特性量測技術。科儀新知，(181)，28-37。https://doi.org/10.29662/IT.201104.0003
- 張明偉（2009）。銅銦鎵硒薄膜太陽能電池吸收層材料性質分析之研究〔碩士論文，元智大學〕。華藝線上圖書館。https://www.airitilibrary.com/Article/Detail?DocID=U0009-2707200915023600
- 邱冠霖（2016）。Preparation and Characterization of Iron-ion Doped Copper Indium Gallium Diselenide Solar Cells〔碩士論文，國立臺灣大學〕。華藝線上圖書館。https://doi.org/10.6342/NTU201602350