Water Vapor Doped TCO Films and Application to Silicon Heterojunction Solar Cells

In this work, we demonstrate the application of water vapor doped indium oxide, alloyed with transition metal element M (IMO), as highly transparent conductive oxide (TCO) films incorporated in bifacial silicon heterojunction (SHJ) solar cells. By adding water vapor and oxygen gas into sputtering gas mixture, both electrical and optical properties of IMO film can be improved significantly. IMO films are characterized by sheet resistivity, Hall mobility and carrier density, crystallinity, and spectral transmittance. Finally, we obtained a 0.64 mA/cm
²
gain in J
_SC
with optimal water vapor doped IMO film on n-side of SHJ cell, resulting in a 0.31% increase in solar cell conversion efficiency.