Jons Bolding studied Applied Physics at the University of Twente in the Netherlands where he focussed on solar energy, with an internship performed at the University of Valencia on perovskite solar cells. Currently he is with SALD B.V. in Eindhoven, the Netherlands, focussing on the development of metal oxide thin films for PV applications using Spatial Atomic Layer Deposition.
Industrially Applicable Spatial Atomic Layer Deposition Of Metal Oxides For Perovskite And Tandem Solar Cells
Spatial Atomic Layer Deposition (sALD) has been employed in high-volume manufacturing in the silicon solar cell industry since 2013, where it has been used for the surface passivation of PERC by thin films of Al2O3. Nowadays, sALD can be utilized in novel perovskite and tandem based solar cells for high-rate (web speed up to 1.5 m/s), large-area (upscalable to 1200 mm wide, also on R2R) deposition of inorganic metal oxides such as among others SnO2, Al2O3, AZO, NiO, and TiO2. In this work, we demonstrate how s-ALD can be used to deposit SnO2, Al2O3, and AZO at high throughput. SnO2 is a promising material for the electron transport layer as it acts as a buffer layer and protects the sensitive layers from generally harsh deposition conditions of the top TCO. Furthermore, recently, more attention is paid to passivating defects at the perovskite to boost the performance and Al2O3 shows great potential passivating surface defects by employing ultra-thin layers. But Al2O3 not only acts as a passivation layer, it is an excellent candidate to encapsulate flexible PV by acting as a barrier layer to undesired degradation mechanisms. And ultimately, AZO is investigated as recombination junction (RJ) to replace the commonly used In-based layers. We demonstrate that a thin layer of AZO improves the performance of the SHJ and TOPCon bottom cell, enabling the fabrication of efficient tandem devices. Spatial ALD matures the tandem technology by employing sustainable and abundant materials at a low cost and large scale, satisfying the demands of industry.
