The Raman spectra of unintentionally doped gallium nitride (GaN) and Mg-doped GaN films were investigated and compared at room temperature and low temperature.
This results not only in quantitative differences in their characteristics but also in a qualitatively different change in the properties of these materials on nitriding.
It was observed that at a nitriding temperature of ~1000 °C films are formed with typical growth characteristics in the form of hexagonal pyramids separated by a smoothed surface.
It is shown that thermal nitridation of the surface layers of the glass samples at a temperature of 375-495°C and a pressure of 0.1-1.0 MPa for 1-20 h brings about the breaking of the Si-O-Si bonds and the formation of the Si-N-Si and Si-N bonds.
The degree of structural transformation in the surface layer depends on the conditions of thermal nitridation and on the chemical composition of the glass.