Homoepitaxial growth rate measurement and surface morphology monitoring of MOVPE-grown Si-doped (100) β-Ga2O3 thin films using in-situ reflectance spectroscopy

We investigate Si-doped beta-Ga2O3layers grown by metalorganic vapor phase epitaxy (MOVPE) on (100)beta-Ga2O3 semi-insulating substrates with the reflection spectrum incident normally onto the substrate surface. The reflectance spectrum transformed into the autocorrelation domain shows a more pronounced Fabry-Pe ' rot oscillation than the raw spectrum, from which one can easily estimate the growth rate and the growth mode based on the period, and the damping behavior of the spectrum, respectively. The observed oscillation con-tributes to the refractive index difference between the bulk substrate and the grown film caused by the incor-porated impurities and different preparation techniques. The high sensitivity of the reflectance spectroscopy is demonstrated to be an advantage as a powerful growth process monitoring tool.

Automated summary

Si-doped beta-Ga2O3 layers were grown on (100) beta-Ga2O3 semi-insulating substrates by MOVPE, and their reflection spectrum on the substrate surface was investigated. Transforming the reflectance spectrum into the autocorrelation domain revealed a more pronounced Fabry-Pe 'rot oscillation, which allowed for easy estimation of the growth rate and growth mode based on the period and damping behavior of the spectrum. The observed oscillation contributed to the refractive index difference between the substrate and the film caused by impurities and preparation techniques. The high sensitivity of reflectance spectroscopy demonstrated its advantage as a powerful growth process monitoring tool.