MOCVD Epitaxy Of Aluminum Gallium Oxide Thin Film Material

Gallium oxide,as a new type of wide band gap semiconductor material,has a large band gap and a high breakdown electric field strength,which has great application prospects in power devices.The(AlxGa1-x)2O3 ternary alloy formed by doping aluminum can achieve band gap regulation,make it have a larger band gap,and the device made of it has a higher breakdown voltage,which is a recent research hotspot.This article systematically investigates the MOCVD epitaxial growth of(AlxGa1-x)2O3 thin films on sapphire and gallium oxide substrates.The effects of growth temperature,oxygen flow rate,and chamber pressure on the quality of thin films were explored;Analyzed the band gap calculation method and growth mechanism of aluminum gallium oxide thin films,and successfully prepared aluminum gallium oxide/gallium oxide multi-quantum well structures.The effects of growth temperature,oxygen flow rate,and chamber pressure on material growth during the epitaxial process of aluminum gallium oxide thin films on sapphire substrates were systematically studied.Research has found that under lower growth temperature conditions,Al atoms are more likely to enter the lattice.At a flow rate of 40 sccm for TMAI,(AlxGa1-x)2O3 with 13.11%Al component was grown.However,at this temperature,the metal organic source reaction was not thorough,resulting in the appearance of clusters on the surface.As the temperature increases,although the Al component of the sample decreases,the crystalline quality of the film improves and the surface roughness also decreases.A lower oxygen flow rate helps to improve the crystallization quality of the film,but it has no effect on surface roughness of the film.Research has found that chamber pressure also has an impact on material quality.The lower the chamber pressure,the more conducive it is to improving the deposition rate and crystallization quality of the film.We studied the X-ray photoelectron spectroscopy(XPS)band gap calculation method and growth mechanism of epitaxial(AlxGa1-x)2O3 thin films on gallium oxide substrates.The band gap of the sample was calculated using the O 1s core energy level spectrum and energy loss spectrum in the XPS spectrum,and the results were basically consistent with the results calculated by XRD using the Vegard law.We systematically studied the epitaxial growth of aluminum gallium oxide thin films on gallium oxide substrates.A step-bunch growth mode has been proposed,which will make the sample surface smoother.Research has found that Al atoms can provide preferential nucleation sites for Ga atoms,suppress island growth modes,and thus reduce film roughness.A(AlxGa1-x)2O3/Ga2O3 multi quantum well structure was successfully prepared using gallium oxide as the substrate.The existence of this structure was demonstrated through XRD patterns,and it was demonstrated through TEM that the structure has a good interface.