Structural, electrical, and optical properties of Zn–In–Sn–O films for silicon heterojunction solar cells

Abstract

We investigated the structural, optical, and electrical properties of Zn–In–Sn–O (ZITO) films prepared by RF magnetron sputtering for silicon heterojunction solar cells. The effects of Zn addition on the properties of the as-grown films were examined. XRD patterns of the ZITO films deposited at room temperature showed a broad peak. The cross-sectional TEM image of ZITO films at low Zn levels exhibited a typical fine or nanostructure embedded in an amorphous phase. On the other hand, at higher Zn addition, the films exhibited a completely amorphous phase. The carrier concentration decreased with increasing Zn content. The lowest electrical resistivity of 5.5×10-4Ωcm was observed for a ZITO film with 4.83 Znat.%. All ZITO films grown in this study showed transmittance of over 80% in the visible and near-infrared spectral range. The absorption was less than 5% in the visible region.