Reduction in Indium Usage for Silicon Heterojunction Solar Cells in a Short-Term Industrial Perspective

Herein, the interest of a sputtering power reduction during physical vapor deposition (PVD) of the rear side indium-based transparent conduction oxide (TCO) is investigated to reduce the In consumption in silicon heterojunction (SHJ) solar cells. Halving the supplied power allows for a TCO thickness reduction of 50%. Process fine-tuning is shown to retain satisfying TCO electrical properties, thus preventing unwanted additional resistance losses despite the drastic reduction in TCO thickness. The produced SHJ solar cells with a 50% reduced TCO thickness show similar performances to those made with the reference process. Using thinner TCO layers at the cell backside is, however, found to come with a bifaciality penalty, which is discussed in detail.

Automated summary

This study investigates the impact of reducing the sputtering power during physical vapor deposition (PVD) of the rear side indium-based transparent conduction oxide (TCO) on the In consumption in silicon heterojunction (SHJ) solar cells. Halving the supplied power allows for a 50% reduction in TCO thickness. Process fine-tuning enables the retention of satisfactory TCO electrical properties despite the drastic reduction in thickness. Although solar cells with reduced TCO thickness show similar performances, there is a bifaciality penalty associated with using thinner TCO layers at the cell backside.