Conferences and exhibitions

The EU PVSEC is the largest international conference for photovoltaics in the areas of research, technologies and applications with an accompanying industrial exhibition, in which representatives of the photovoltaic industry present their technologies, innovations and new concepts.  This year the EU PVSEC will again be held online. Dr. Volker Sittinger, head of the Department Diamond-based Systems and Applications at the Fraunhofer IST will present his latest research results in the field of photovoltaics:

»Development of indium zinc oxide TCOs films deposited from a metallic tube target for perovskite-silicon tandem solar cell applications«

Abstract:

This work focuses on the development and optimization of indium zinc oxide (IZO) as top transparent conductive oxide (TCO) for use in perovskite-silicon tandem solar cells. The indium zinc oxide films were produced by means of a reactive sputtering process with indium zinc alloy rotatable target with 96/4 weight percent. The coatings were produced on a large area in-line coater (1 m x 0.6 m) to demonstrate the process capability for industrial application. The indium/zinc rotatable target was sputtered with argon as sputter gas, and oxygen as reactive gas. The layer preparation was done with a lambda sensor to keep the oxygen partial pressure constant during the process. The IZO films were optimized for conductivity, carrier mobility and absorption. The measured absorption of the films was weighted with global standard spectral data (AM1.5G) in order to more closely mimic the effect of absorption on the resulting solar cell efficiency. The optimized IZO films will then deposited onto perovskite-silicon tandem cells where the power conversion efficiencies (PCE), short-circuit current densities (Jsc), open-circuit voltages (Voc), and fill factors (FF) were characterized and compared with tandem cells with a reference ITO as top TCO.