Crystalline films of periclase and β-MgO with or without Mg(OH)2 were deposited on soda lime glass substrates by a sol-gel process using magnesium acetate [Mg(CH3COO)2·4H2O]. MgO films were annealed by RTP under various atmospheres (Ar, H2 and O2) at 500 for 5 minutes and the crystallization of MgO was examined according to the RTP conditions and the cleaning methods of the glass substrates. The degrees of crystallization of MgO films were dependent on the RTP conditions and the cleaning methods of the glass substrates. An MgO film which was annealed by RTP under an O2 atmosphere and a cleaning method of CM2, showed good crystallization of periclase-MgO and β-MgO, and Mg(OH)2 phase was not observed. When the electric field was increased, the dielectric constant approached 8.2 with a dissipation factor of 2.3%. With an increase in the frequency, the dielectric constant decreased slowly until the dissipation factor increased at the dispersion frequency. All the MgO films were highly transparent (above 90%) and the refractive index of MgO film with thickness of 250 nm approached 1.71.

Keywords: MgO film, Rapid thermal processing (RTP), Periclase-MgO, β-MgO, Optical property.