Microstructure and Optical Properties of Zn(O,S) Thin Films Prepared by Radio Frequency Magnetron Sputtering

• Main Authors: Bing-Hau Kuo, 郭柄豪
• Other Authors: Fuh-Sheng Shieu
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/13188209551021189521

碩士 === 國立中興大學 === 材料科學與工程學系所 === 101 === Cu(In,Ga)Se (CIGS) solar cell is one of most promising material in thin film solar cell. The chemical bath deposition CdS is typically used as buffer layer in high efficiency solar cell. However, Cd is very toxic and taken consideration in great impact to environment. It is quite important issue for mass production to search Cd-free alternated buffer layer and develop all-vacuum process in the future. A series of ZnO1−xSx films prepared by radio-frequency reactive magnetron sputtering on soda-lime glasses as substrates. The composition, structure, and optical properties of the films deposited at different RF power, O2/(Ar+O2) ratio and substrate temperature were studied. The structure of the films deposited under various process parameters was characterized by XRD revealed that the films are wurtzite structure. The XRD peak shift to lower angle position with increasing RF power. The layer composition show that oxygen concentration decrease from 12.63 to 7.61 at.% and sulfur increase from 35.98 to 40.71 at.% as RF power increases. The optical absorption edge shift from 4.12 to 3.88 eV (red shift effect). Amorphous structure was found as O2/(Ar+O2) excess 4%. ESCA show the content of oxygen increase from 10.79 to 62.31 at.% and sulfur decrease from 40.35 to 4.55 at.% with oxygen flow increase. The optical transmission spectra show absorption edge shift 4.03 to 4.17 eV (blue shift effect). The XRD peak shift to higher angle was observed as substrate temperature increased. From TEM observation, the films were wurtzite structure with (002) preferred orientation. The optical absorption edge shift from 4.10 to 4.03 eV (red shift effect).