Cu(In, Ga)Se2 Thin Films on Flexible Polyimide Sheet: Structural and Electrical Properties versus Composition

• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2009,（2）
• 页码范围: 215-218
• 页数: 4页
• 语种: 英文

摘要

The structural and electrical properties of Cu(In,Ga)Se2 (CIGS) films grown on polyimide (PI) sheet using the three-stage co-evaporation process are investigated by x-ray diffraction spectra (XRD), scanning electron microscopy (SEMI), Raman spectra, and Hall effect measurements, respectively. The results show that the prop-erties of CIGS films on PI sheet are strongly dependent on the compositional ratio of Cu/(In+Ga) (Cu/Ⅲ). In contrast to the non-stoichiometric CIGS films, stoichiometric CIGS films show better structural and electrical properties, such as a relatively larger grain size, lower resistivity and higher carrier concentration. The flexible CIGS solar cells on PI sheet with the conversion efficiencies of 9.7% and 6.6% are demonstrated for the CIGSabsorber layer with Cu/Ⅲ of 0.96 and 0.76, respectively (active area, 0.20cm2). The cell efficiency for Cu-poor CIGS films is limited by a relatively lower open circuit voltage and fill factor.