Study of refractive index variation of high K dielectric material magnesium oxide

The change of refractive index of magnesium oxide with uniaxial and biaxial pressurization was calculated by using the first nature principle, and it was found that the dielectric constant decreased by pressurization, and the biaxial pressurization changed magnesium oxide from negative uniaxial crystal to positive uniaxial crystal.

Magnesium oxide has many excellent properties, such as electrical insulation, chemical inertness, mechanical stability, high temperature stability, thermal conductivity and high efficiency of secondary electron emission, and is widely used in many fields such as optical films, and high critical temperature superconducting buffer layers, large area flat panels, plasma display devices, high K insulating layer dielectric materials, etc. Magnesium oxide is chemically inert, with a forbidden band width of 7.8 eV and an intrinsic material permittivity of 9.8, and is selected as a high K dielectric

material, which can be used in MOSFETs to replace SiO2 as a new insulating layer dielectric. The optical and electrical properties of MgO thin

films as well as the film thickness are of great importance for the fabrication and characterization of these optoelectronic devices, and therefore these become the focus of this paper.

 

In this thesis, thin (about 10 nm) MgO films were grown on silicon and sapphire by metal organic chemical vapor deposition (MOCVD) and RF magnetron sputtering (R.FMagnetron Sputtering), respectively, and the films were examined by X-ray electron spectroscopy (XPS), X-ray diffractometry (XRD), and scanning electron microscopy (SEM).