A research team, led by Germany's Fraunhofer Institute for Solar Energy Systems (ISE), studied two stages of cell manufacturing that are among the most in need of optimization due to growing concerns over the availability of the commonly used indium and silver: transparent conductive oxide deposition and cell metallization.

The research takes processes used in silicon heterojunction (HJT) cell manufacturing as a starting point, and examines how the addition of a perovskite top cell would change the requirements for the rest of the cell structure.

Solliance recently announced that a collaboration with the M2N group of René Janssen at University of Technology Eindhoven has resulted in two world-records for 4T perovskite tandems.

The partners reported that they further optimized the wide-bandgap (1.69eV) perovskite cells with high near-infrared transparency for 4T tandem applications. The perovskite cell has reached a stabilized efficiency of 17.8% during 5-min maximum-power-point tracking. In combination with the Panasonic silicon bottom cell, a new world-record 4T perovskite/Si tandem efficiency of 29.2% was realized.