電極結構對DLC太陽能電池之影響及特性分析

Fabrication and Characterization of the Electrodes on DLC Solar Cells

黃昱哲(Yu-Che Huang)

指導教授 ： 王錫九

國立臺北科技大學/工程學院/材料及資源工程系研究所/碩士(2010年)

https://doi.org/10.6841/NTUT.2010.00555

摘要

人類在工業革命之後，為了提升居住生活品質，大量開發地球上所蘊藏的資源，不過也連帶對地球產生不利的效應，不僅有能源供應短缺問題，也引發地球環境汙染。太陽能電池可將光能轉換電能，因此可趨緩能源短缺及環境汙染問題。本研究以磁控濺鍍法，沉積高透光性及高導電性的ITO (Indium Tin Oxide) 透明導電薄膜，其主要目的為有效率收集太陽能電池元件照光後所生成的電荷載子，並設計電極的排列方式搭配先前製備p型類鑽碳 (Diamond like-Carbon，DLC)太陽能電池之參數，探討電池轉換效率。ITO薄膜之電阻率以薄膜厚度為80 nm時最佳。在光學性質表現上，DC 40 W膜厚80 nm的穿透率為最佳，約93%，能隙大約3 eV 左右。ITO薄膜應用於太陽能電池的光學性質是很重要的參數之一，當可見光波長經過ITO薄膜時，有高的穿透率是必然的，因此本研究選用濺鍍功率DC 40 W厚度80 nm的ITO薄膜，應用於p-DLC太陽能電池。由研究結果得知，未沉積ITO薄膜的電池結構所表現出的效率為最差；而電池結構以ITO/p-DLC/n-Si/Al的元件效率為1.22%，因元件接面空乏區所產生之電子電洞對，可藉由ITO薄膜達到全面性收集電荷載子。但其材料阻抗仍然過高，串聯電阻為32.26 Ω，導致無法有效率將電荷載子輸出；電池結構Al/ITO/p-DLC/n-Si/Al，轉換效率則可達3.41%，其電荷載子一開始先透過ITO薄膜收集，再經由更低電阻率之Al指狀電極收集電荷載子，而從I-V圖上之斜率求得串聯電阻，其值約為8.81Ω；Al/ITO/p-DLC/n-Si/Al太陽能電池的量子效率在波長700 nm時可獲得較高之量子效率，約76%。

關鍵字

類鑽碳薄膜 ； ITO透明導電薄膜 ； 電極結構 ； 太陽能電池 ； 轉換效率

並列摘要

After the industrial revolution, a large number of the hidden resources on the earth are developed to enhance the quality of human life. However, the side effects of these actions induce not only the shortages of fossil energy but also the environmental pollution on the earth. Solar cells convert light into electrical energy which can slow down these issues. The high light transmittance and electric conductivity of indium tin oxide (ITO) films are deposited by DC magnetron sputtering method, the main purpose of efficient collection of solar cells after light illumination generated by the electrical carriers, which is designed as the electrodes of p type DLC (Diamond like-Carbon) solar cells to enhance the conversion efficiency of the battery. The optimal properties of ITO films prepared by 40W are 80 nm that the optical transmission and energy band of the films are about 93% and 3 eV, respectively. The optical properties of ITO thin films applied on solar cell are very important. For the visible light to pass through the ITO thin film, high transmittance of the material is essential. In this study, an 80nm thick ITO thin film prepared with 40W sputtering power is applied on the p-DLC solar cell. Result indicates that solar cell without ITO thin film deposited in its structure possesses lowest efficiency. As compared with metal electrode with finger shape directly onto the p-DLC/n-Si devices, devices with ITO/p-DLC/n-Si/Al show 1.22% conversion efficiency for more light absorbed by the devices and more photo-generation carriers effectively collected by the ITO electrode. Even though the ITO thin films could collect photo-generation carriers, the series resistance of ITO electrode with about 32.26 Ω is still too high for the cell performance. The structure of cell with Al/ITO/p-DLC/n-Si/Al is 3.41% of the conversion efficiency possibly due to the lower resistivity of the Al finger electrodes series connected with modified parallel ITO electrodes onto P-DLC film. The series resistance of the combined electrodes in this device computed by the I-V curve is about 8.81 Ω. The maximum of quantum efficiency of Al/ITO/p-DLC/n-Si/Al solar cell is at the wavelength of 700 nm and about 76%.

並列關鍵字

Diamond-like carbon ； ITO thin film ； Electrodes structure ； Solar cell ； Conversion efficiency

參考文獻

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