CIS薄膜太陽能電池之Mo背電極和CIS薄膜的製造與特性分析

The fabrication and analysis of Mo back electrode and CIS thin film of a CIS thin film solar cell

陳宏恩(Hung-En Chen)

指導教授 ： 黃景良

共同指導教授 ： 于劍平(Jiahn-Piring Yur)

崑山科技大學/工程學院/機械工程研究所/碩士(2008年)

摘要

本研究主要以真空濺鍍機(Sputter)與電子束蒸鍍機(EBE)系統成長Mo/Cu-In層，再以硫化法成長CuInS2薄膜。製程方面除了硫化法於大氣環境下進行外，其餘皆在低真空環境中採取物理氣相沉積法(PVD)成長薄膜。本實驗研究方法不同於傳統以共蒸與硒化法製造CuInSe2薄膜，可大幅的降低製造成本與製程時間。
由於CIS薄膜太陽能是利用Mo金屬薄膜來當作太陽能元件的背電極，主要功用是作為歐姆接觸。本實驗使用濺鍍功率100W到600W將Mo薄膜沉積在玻璃基底。由膜厚分析中發現，以600W所鍍製之Mo薄膜表面均勻性較佳。並藉由電性分析得知，Mo薄膜與CuInS2薄膜為歐姆接觸。另外在硫化部分，以425℃硫化60分鐘與90分鐘可得到較均一的CuInS2的相。不過In在硫化的過程中，會因為硫化時間的增加與硫化溫度升高而加快流失。導致硫化後的CuInS2峰值強度降低，不過可藉由調高預沉積Cu-In層的In的比例來解決問題。CuInS2薄膜經由電性量測結果顯示為P-type，載子濃度、遷移率與片電阻，各在1019~1020(cm-3)、10-2~10-1(cm2/V-sec)與10~102(Ω/cm2)之間，與文獻資料相差不大，故確定本研究方法的可行性。

關鍵字

CuInS2 ； CIS ； 硫化法

並列摘要

This study is to deposit the Mo/Cu-In layer by using the vacuum Sputter and Eelectron Beam Evaporation(EBE) system, then sulfur into CuInS2 thin film. This fabrication adopts PVD method under low vacuum environment except the sulfur method under atmosphere pressure. This experimental fabrication is different to the conventional method which used Coevaporation and Selenization to fabricate the CuInSe2 thin film, it can reduce the cost and fabrication time from the present method.
Because Mo layer is conventionally used as a back electrode for CIS solar cell, its main function is used as Ohm contact. This experiment uses power of 100 to 600 watt to sputter the Mo layer on glass subtract. It is found from α-step (thin film thickness) analysis that the better uniformity of Mo thin film can be obtained by using power of 600 watt. And based on the electricity characteristic analysis, it is proved that the present Mo layer and CuInS2 thin film is belong to Ohm contact. For the sulfur part, use 60 and 90 minutes as well as 425℃ can obtain better uniformity of CuInS2 phase. But In will be reduced during the sulfur process, the higher the temperature and longer the sulfur time, the worse reduction of In will be. It results in the strength reduction of CuInS2 peak. This problem can be solved by adjusting bigger proportion of In of the pre-deposited Cu-In layer.
The present CuInS2 thin film is measured as P-type layer. Its carrier concentration, mobility and film electric resistance are 1019~1020(cm-3), 10-2~10-1(cm2/V-sec) and 10~102 (Ω/cm2), respectively. It is not big difference from the previous results. Thus, the method shown in present investigation is feasible.

並列關鍵字

CuInS2 ； CIS ； Sulfurization

參考文獻

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