二硫化銅銦鎵薄膜太陽光電吸收層製程及後處理之研究

Study on the fabrication and post-treatment of absorption layer for a CuInGaS2 thin film solar cell

王懋竣(Mao-Chun Wang)

指導教授 ： 黃景良

崑山科技大學/工程學院/機械工程研究所/碩士(2012年)

摘要

CIGS太陽能電池在眾多薄膜光伏材料中，顯示出相當多的優勢。例如：吸收系數高、轉換效率高，對於大部分太陽光之波長都能吸收。CIGS製程方式較常見的多屬於在真空環境下完成，其銅、銦、鎵是以共蒸鍍(Co-evaporates)或濺鍍(Sputter)的方式製成合金薄膜，再將此薄膜在硫蒸氣壓下進行退火，即完成CIGS2結構。
本研究主要是採用Cu/Ga合金靶與In靶，以雙靶磁控濺鍍方式成長Cu/Ga-In薄膜，並將Cu/Ga-In預製薄膜前驅疊層區分為Cu/Ga疊In及In疊Cu/Ga結構，以Bilayer與Multilayer的四種疊層方式呈現，藉由硫化過程成長CIGS薄膜。
Cu/Ga靶以350W均勻性最好，故本實驗採用350W為我們的功率參數。In靶以400W成長的薄膜表面均勻性與粗糙度都在可接受範圍內，能於較短時間內成長至所需膜厚，但與250W比較起來卻是更為粗糙，故我們以250W做為成長In薄膜的最適當參數。藉由實驗分析結果得知以Bilayer與Multilayer鍍製的金屬前驅層Cu/Ga與In的成分比例為1:2較佳，由EDS分析結果得知在Cu/Ga：In比例1:2所鍍製出來的金屬前驅層所形成的CIGS薄膜成分比例較佳，成分比例接近於1:1:2(理想成分比例)。由XRD繞射分析可得到CIGS優選結晶方向(112)的峰值，其中又以Multilayer的疊層方式能獲得結晶顆粒較大且結晶緻密的CIGS薄膜。

關鍵字

銅銦鎵硫 ； 磁控濺鍍 ； 硫化法 ； 合金靶

並列摘要

CIGS solar cells show a considerable number of advantages among a number of thin-film photovoltaic materials. For example: the high absorption coefficient, high conversion efficiency, can absorb most wavelength sunlight. The fabrication process of CIGS is mostly done in a vacuum environment. The alloy thin-film of copper, indium and gallium is made by co-evaporating or sputtering, then this alloy thin film is annealed in sulfur vapor pressure to complete CIGS2 structure.
Using 350W power can obtain the best uniformity for the copper gallium target, thus the experiments use the 350W as the power parameter. The thin film surface homogeneity and roughness are within an acceptable range by using 400W power for indium target, and it can be grown in a relatively short period of time to the desired thickness. But it is rougher comparing with the 250W power, thus the 250W power is applied as the most appropriate parameter for indium target. Analysis results indicated that better composition ratio of the bilayer and multilayer coated metal precursor layer of copper gallium and indium is 1:2, and EDS analysis results indicated that the ratio of Cu/Ga:In of 1:2 deposited by the experiments is the better CIGS thin film composition ratio, the composition ratio of Cu:Ga:In close to 1:1:2 (ideal composition ratio). The XRD diffraction analysis of the available CIGS preferred crystallographic orientation (112) peak, and multilayer laminated can get larger and dense crystalline layer of the metal precursor layer.

並列關鍵字

CIGS2 ； Magnetron sputtering ； Sulfurized method ； Alloy target

參考文獻

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