Abstract For a development of base layers for promising solar cells with extremely thin absorbers (ETA) low cost electrodeposition methods for sequential large-scale production of one-dimensional ZnO nanostructures and Se thin films with little material waste were investigated. Research of structure and optical properties of Se and ZnO have allowed us to choose electrolytes and modes in which electrodeposition of selenium was not accompanied by ZnO destruction. It was revealed that annealing of ZnO/Se samples using a halogen lamp provides conversion of amorphous selenious films into suitable for solar cells gray nanocrystalline hexagonal Se without ZnO degradation and thus enables the formation of bases of ETA solar cells.