ABSTRACT
Magnesium oxide (MgO) has a simple rock salt crystal structure with an extremely high melting temperature of 2800°C. It also shows low secondary electron emission, very low standard free energy, and relatively low dielectric constant of 9.8. Due to these physical and chemical properties, single crystal MgO is used as a substrate, for example, for epitaxial growth of low-Tc . (NbN) or high-Tc (YBCO) superconducting films. There is also interest in using MgO thin-films as buffer layers for the growth of high quality NbN or YBCO films on silicon and in futuristic device applications where a superconductor and a semiconductor coexist on the same substrate. Various deposition methods, e.g. electron beam deposition, rf-sputtering, chemical vapor deposition, and pulsed laser ablation techniques, have been used to achieve desired film quality.
