CIGS太陽能電池之MgxZn1-xO緩衝層材料研究

Studies of CIGS Solar Cell with MgxZn1-xO Buffer layer Material

鄭凱鴻(Kai-Hung Cheng)

指導教授 ： 蒲念文

元智大學/電機通訊學院/光電工程學系/碩士(2013年)

https://doi.org/10.6838/YZU.2013.00335

摘要

摘要
為發展全真空製程本研究使用RF磁控濺鍍方式來製作氧化鎂鋅(Mg0.1Zn0.9O， MZO)薄膜，以替代CdS緩衝層做為CIGS太陽能電池的無毒性緩衝層材料。其研究探討可分類成MZO薄膜性質分析與元件光電轉換效率兩個部分。然而，本研究主要以調整濺鍍製程條件，如製程功率、工作氣體壓力等方式來沉積MZO薄膜。在元件光電轉換效率方面，以MZO薄膜實際製作於CIGS太陽電池緩衝層上，來進行元件特性討論和效率評估。當中可藉由控制溫度條件、退火條件等參數，以消除製程中的缺陷促進晶粒成長，進一步改善薄膜光電特性以及元件效率。
分析中使用霍爾量測與紫外-可見光譜儀進行MZO薄膜之載子濃度、電阻率以及光學特性，藉由XRD與SEM觀察薄膜結構和表面形貌。預期完成1吋面積玻璃基板的CIGS太陽電池，並以I-V量測進行元件特性探討。

本實驗中製作出MZO緩衝層2.5mTorr、5 mTorr、10 mTorr，在三種不同壓力下的CIGS太陽能電池，在AM1.5，100mW/cm2標準光源下，其2.5mTorr在75W有最高效率1.48%，開路電壓為0.275V，短路電流密度為0.0436mA/ cm2，填充因子為29.66%。而5mTorr壓力下，在125W有最高效率0.99%，開路電壓為0.177V，短路電流密度為0.005mA/ cm2，填充因子為27.92%。在10mTorr壓力下，在125W有最高效率1.79%，開路電壓為0.223V，短路電流密度為0.006mA/ cm2，填充因子為33.41%。

關鍵字

CIGS太陽能電池 ； 緩衝層 ； RF磁控濺鍍 ； 氧化鋅鎂

並列摘要

Abstract

To develop full vacuum process, this research uses RF magnetron sputtering to produce MZO thin films as non-toxic buffer layer materials based on CIGS solar cells in the place of the buffer layers based on CdS solar cells. This research can be classified into the analysis of MZO thin film properties and the efficiency of photoelectric conversion elements; while it mainly focuses on the deposition of MZO thin films through the conditions of adjusting magnetron sputtering, such as the process power, the operating gas pressure. With regard to the efficiency of photoelectric conversion elements, we will discuss the element properties and evaluate their efficiency given the MZO thin films being used in fabricating buffer layers based on CIGS solar cells. In the meantime, both the optimal property of thin films and element efficiency are likely to be improved through the control of parameters such as fixed temperature and annealing temperature to get rid of any flaws in the course of processing, thus furthering the optimal property of thin films and element efficiency.
In the analysis, Hall measurements and ultraviolet are used, so that carrier concentration of MZO thin films, resistivity and optical properties can be seen via spectrum meters with the hope of observing the structure of thin films and their surface morphology with XRD and SEM. This research expects to complete one-inch area of glass substrate for CIGS solar cells and go on to discuss element properties by measuring I-V characteristics.
Three different 2.5mTorr, 5mTorr, 10mTorr MZO-based buffer layers are produced in this experiment. Under the three different pressures, the one under 75W, the highest efficiency of 2.5mTorr-based IGS solar cell reaches 1.48%, with the open circuit voltage at 0.275V, short circuit current density at 0.0436mA/cm2, while the fill factor being 29.66%. The one under 125W, the highest efficiency of 5mTorr reaches 0.99%, with the open circuit voltage at 0.177V, short circuit current density at 0.005mA/ cm2, while the fill factor being 27.92%. The one under 125W, the highest efficiency of 10mTorr reaches 1.79%, with the open circuit voltage at 0.223V, short circuit current density at 0.006mA/ cm2 , while the fill factor being 33.41%。

並列關鍵字

CIGS Solar Cell ； Buffer Layer ； RF Sputter Magnetron ； MgZnO

參考文獻

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