應用於銅銦鎵硒薄膜太陽能元件之吸收層製程技術開發與研究

Abstract

銅銦鎵硒是一種具有潛力的薄膜太陽能電池吸收層材料。然而，因其為複雜的多元元素組成，二元相的生成尚未被有效地控制及理解，目前仍未有一標準且適合量產化的製程。本論文經由銅硒及銦硒二元化合物的研究結果，提出了一種適合量產且容易進行的硒化製程。論文中針對二元相的生成有詳細地探討，透過二元相的研究分析銅銦鎵硒四元相可能的成長路徑。經由二元相的研究結果設計由β-Cu2-xSe及γ-(In,Ga)2Se3所形成的銅銦鎵硒薄膜具有良好的特性，包含附著性佳、平整的表面形態、及均勻緻密且大顆的晶粒，其優選晶相為(220/204)/(112)。由X光繞射分析的結果，兩晶相強度的比值(220/204)/(112)為0.94。此外，論文中所提出的硒化製程法也減緩了在典型一階段硒化製程所製作出的銅銦鎵硒薄膜會遇到的化學劑量組成比及殘餘二元相的問題。

Cu(In,Ga)Se2 (CIGS) is the promising material for thin-film solar cell technology. However, lack of feasible fabrication process for mass-production and complicated binary phases in the CIGS films are the issues limiting the practical applications of CIGS. An simple selenization process was proposed according to the investigation of the Cu-Se and In-Se binary phases. The details on the formation of the binary phases as well as the formation path of CIGS are presented. The resulted CIGS films grown by the formation path of β-Cu2-xSe + γ-(In,Ga)2Se3 exhibited good adhesion, smooth surface, as well as large, uniform, and densely packed crystals with preferred (220/204)/(112) orientation. The ratio of (220/204)/(112) was 0.94. In addition, the issues of non-stoichiometric elemental composition and remaining binary phases found in the typical one-step selenized CIGS thin films were mitigated.