Abstract: A multi-junction photovoltaic device comprising a layer of metal oxynitride between a first sub-cell and a second sub-cell is disclosed, the first sub-cell having a layer comprising a perovskite light absorber material. In addition, a method of manufacturing said multi junction photovoltaic device is disclosed. The metal oxynitride is preferably titanium oxynitride. Advantageously, the device may be produced in a simple, fast, consistent and inexpensive manner, whilst the properties of the titanium oxynitride layer may be tuned to avoid the occurrence of local shunt paths and to reduce reflection losses.

Abstract: In a method for producing a I-III-VI compound semiconductor layer, a substrate is provided with a coating which has a metallic precursor layer. The coating is kept, for the duration of a process time, at temperatures of at least 350 degrees C. and the metallic precursor layer, in the presence of a chalcogen at an ambient pressure of between 500 mbar and 1500 mbar, is converted into a compound semiconductor layer. The coating is kept at temperatures for the duration of an activation time which attain at least an activation barrier temperature, whereby as the activation barrier temperature a value of at least 600° C. is selected.

Abstract: In a method for producing a I-III-VI compound semiconductor layer, a substrate is provided with a coating which has a metallic precursor layer. The coating is kept, for the duration of a process time, at temperatures of at least 350 degrees C. and the metallic precursor layer, in the presence of a chalcogen at an ambient pressure of between 500 mbar and 1500 mbar, is converted into a compound semiconductor layer. The coating is kept at temperatures for the duration of an activation time which attain at least an activation barrier temperature, whereby as the activation barrier temperature a value of at least 600° C. is selected.

Abstract: A method deposits a layer of an indium chalcogenide onto a substrate. The method includes the steps of: providing an indium source in a reaction zone, providing a gaseous source of a chalcogen in the reaction zone, and heating the substrate. Thereby in the reaction zone, at a pressure of approximately atmospheric ambient pressure, the indium originating from the indium source and the chalcogen originating from the source of a chalcogen are converted to an indium chalcogenide being deposited onto the surface of the substrate.