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 x 10(-4) Omega cm was observed for a ZITO film with 4.83 Zn at.%. 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. (C) 2015 Elsevier B.V. All rights reserved.