Oxygen-dependent epitaxial growth of Pt(001) thin films on MgO(001) by magnetron sputtering

Abstract

The roles of oxygen gas in crystal orientation, surface morphology and electrical resistivity of Pt thin films grown on MgO(001) substrate by magnetron sputtering are studied. With a well-controlled oxygen ratio (15% oxygen) during sputtering deposition with Ar-O2 mixture ambient, (001) epitaxial growth of Pt film on MgO substrate is achieved with an epitaxial orientation relationship of (001)Pt//(001)MgO and [100]Pt//[100]MgO. Microstructural and electrical characterizations reveal that the (001) Pt thin films possess very smooth surface and good conductivity. The formation and subsequent decomposition of platinum oxides in the Pt films grown with more than 30% oxygen result in an increase of surface roughness and electrical resistivity. The high-quality Pt(001) film has large potential for integrated electronic device applications.