Room-temperature synthesis of epitaxial oxide thin films for development of unequilibrium structure and novel electronic functionalization

抄録

Epitaxial growth of oxide films at lower temperatures is favored to obtain sharp interfaces and flat surfaces which are of advantage to construct high-quality electronic devices, and also is expected to result in novel development of unequilibrium structure and new electronic functionalization. Pulsed laser deposition (PLD) technique using laser ablation of a solid target is known to reduce the temperature drastically for epitaxial growth because of the highly energetic film precursors ablated from the target. In this article we briefly review the main achievements of our research group on room-temperature (RT, 20°C) synthesis of epitaxial oxide thin films by way of laser MBE process, i.e. PLD in ultrahigh vacuum. RT-epitaxial film growth by laser MBE and its electronic application were presented for some functional oxide thin films such as ZnO, Sn-doped In₂O₃ (ITO), sapphire (α-Al₂O₃), (Li,Ni)O, or (Mg,Ni)O, and also magnetic functionalization via selective post-depositional reduction of complex oxide films was demonstrated.