Transparent Conductive Oxide Materials for Bifacial Heterojunction Back Contact Solar Cells

We assessed the performance of transparent conductive oxide (TCO) materials for use in the heterojunction back contact + (HBC+) solar cell. In addition to indium tin oxide (ITO), titanium dioxide (TiO
₂
) and zinc oxide (ZnO) were evaluated as possible materials for the rear side of HBC+ solar cells. The results showed that the different optical and electrical parameters of the TCO materials affect the cell performance differently. Of the TCO materials that were assessed, the HBC+ cell with TiO
₂
delivered the best performance by increasing the power density by approximately 0.5 mW/cm
²
(relative to our previous evaluation) under bifacial illumination conditions. The optical properties of the TCO materials were revealed to have the greatest effect on the cell performance, particularly on the rear-side performance. The optimal size of the rear metal area is affected by the properties of the TCO material, mainly by the resistive components, and an increase in the temperature does not affect the selection of the best TCO material.