Synthesis and characterization of MgO thin film prepared by sol-gel method

Abstract

One of the most important aspects of sol-gel processing is that the fluid sol or solution is ideal for the deposition of thin films by common processes such as dipping and spinning. The oxide films are characterized by high purity, good homogeneity, and low processing temperature. Another advantage of sol-gel processing consists in that the stoichiometry and porosity of the films are easy to control. MgO thin films were prepared by the spin coating of MgO precursor solution and successive heating. For organic based MgO precursor solution, we used magnesium acetate in 1,3-propanethiol, magnesium methoxide, and ethanol. Spin coating of the solution and subsequent firing produced thin MgO films whose thickness are ranging from approximately 100 A ~ 1000 A. The newly synthesized MgO films were characterized by SEM, IR, AFM, and XRD as functions of solution acidity, volume percentage of magnesium ion in solution, firing temperature, etc. The physical and chemical properties of the MgO films above were also compared with those of thin MgO films produced by magnetic sputtering technique. One of the most important properties of wideband-gap materials such as MgO, secondary-electron emission yields (SEEY) were also measured as a function of the surface condition of the films.