摻雜鈉與硫對太陽電池材料銅銦硒與鉬薄膜之影響與研究

The influence study of doping Na and S in CIS and Mo thin films for solar cell application.

劉勝隆(Sheng-Lung Liu)

指導教授 ： 楊立中

國立虎尾科技大學/電機資訊學院/光電與材料科技研究所/碩士(2008年)

摘要

Mo金屬是CIGS薄膜太陽電池最為廣泛使用在背電極的材料，近幾年鈉離子與硫離子在CIGS太陽電池中的存在被發現是對其轉換效率有正面的提升。本研究使用直流磁控濺鍍法(DC magnetron sputter deposition)，在室溫的環境下將鉬薄膜濺鍍沉積在鈉玻璃基板(SLG)以及1737康寧玻璃上。藉由改變工作氬氣壓來觀察Mo薄膜的表面形態、電阻率以及應力的變化；將兩種不同應力值的Mo薄膜沉積於1737康寧玻璃後再摻雜硫化鈉，來觀察鈉離子與硫離子在Mo薄膜內部的分佈情形。富銅(Cu-rich)與富銦(Cu-poor)的CIS薄膜浸泡摻雜硫化鈉後並退火，利用二次離子質譜儀來觀察鈉離子與硫離子在其內部的擴散分佈情形與影響。
實驗中可以得知，在高氬氣工作氣壓下沉積的Mo薄膜結構會呈現瘦長的且較鬆散的晶粒結構，孔洞較多且電阻率較高，屬於壓縮應力，黏著性較好；在低氬氣工作氣壓下沉積的Mo薄膜結構會呈現較小且密度較緊密的晶粒結構，孔洞也較少且電阻率較低，屬於張應力，黏著性較差。鈉離子與硫離子在張應力型態的Mo薄膜是存在於薄膜表面與薄膜與基板的介面處。鈉離子在富銅與富銦的CIS薄膜內部，經過摻雜與退火後的處理都會有擴散進去的情形產生；硫離子則是在富銅CIS中會有效的擴散，但在富銦CIS內則不會有此現象。

關鍵字

鉬 ； 銅銦硒薄膜太陽電池 ； 硫 ； 鈉 ； 直流磁控濺鍍

並列摘要

Molybdenum material is generally applied on CIGS back contact. Recent year, sodium and sulfur will improve the performance of CIGS solar cell. This research, Mo thin films are deposited on SLG and Corning 1737 glasses in room temperature by DC magnetron sputter deposition.
The Mo thin film of surface morphology、resistivity and variation of stresses are observed by changing Ar working pressure. Na2S is doped into two kinds of stresses Mo thin film which are deposited on corning 1737 in order to understand the distribution of Na and S in Mo thin film. The diffusion of Na and S in CIS (Cu-rich and Cu-poor) thin film are doping Na2S and then annealing which are detected by SIMS. Experiments suggest that Mo thin film in high Ar pressure appears tensile stress as well as have loosely and porous grain structure、high resistivity and good adhesion. In low Ar pressure, Mo thin film appears compressive stress, which have dense and closed grain structure、low resistivity and bad adhesion. Na and S is observed that exist in Mo surface and Mo/substrate interface at tensile Mo. Sodium is diffused into both Cu-poor and Cu-rich CIS thin film after doping Na2S and annealing in 200°C, whereas sulfur is only diffused into Cu-rich CIS.

並列關鍵字

Mo ； CIS thin film solar cell ； sodium ； Sulfur ； DC magnetron sputter deposition

參考文獻

[1] http://www.moea.gov.tw/~ecobook/season/sag3-b2.htm

[2] http://tw.finace.yahoo.com/xp/20050726/50/0112306715.html

[3] 郭民村，由太陽電池製程設備發展台灣太陽能電池產業未來，精　　

密製造與新興能源機械技術專輯。

[4] Yoshihiro Hamakawa, Thin-film Solar Cells, p.24