Hexagonal Boron Nitride Seed Layer-Assisted van der Waals Growth of BaSnO3 Perovskite Films

We have succeededin obtaining BaSnO3 perovskitethinfilms with remarkable near-infrared luminescence by van der Waalsgrowth. The films were grown on quartz glass substrates by pulsedlaser deposition using hexagonal boron nitride as the seed layer,and their crystallinity was confirmed by X-ray diffraction and cross-sectionaltransmission electron microscopy. The near-infrared emission of thegrown film exhibited a broad emission peak centered at 920 nm. Thetransparency of the BaSnO3 film (thickness = 1000 nm)/hexagonal boron nitride /double-sided optically polished quartz glasssubstrate was approximately 90% at approximately 500 nm with or withoutthe BaSnO3 film. Films showing remarkable near-infraredemission and high transparency obtained by van der Waals-type growthcould be used in practical wavelength conversion devices that improvethe efficiency of Si single-crystal solar cells. The hexagonal boronnitride seed layer supporting the van der Waals growth is an effectivemethod for high-quality crystal growth of films. It can be used forperovskite-type oxides with many functionalities.

Automated summary

We successfully obtained BaSnO3 perovskite thin films with remarkable near-infrared luminescence by van der Waals growth. The films were grown on quartz glass substrates using hexagonal boron nitride as the seed layer, and their crystallinity was confirmed by X-ray diffraction and transmission electron microscopy. The grown film exhibited a broad near-infrared emission peak centered at 920 nm. The transparent BaSnO3 film, with high transparency and remarkable near-infrared emission, obtained through van der Waals-type growth, can be applied in wavelength conversion devices to improve the efficiency of Si single-crystal solar cells. The hexagonal boron nitride seed layer is an effective method for high-quality crystal growth of perovskite-type oxides with various functionalities.