Fig. 1. Thickness distribution of GaN thin films at different H₂ carrier gas flow rates

Fig. 2. AFM surface morphology images 5 μm × 5 μm of GaN thin films at different H₂ carrier gas flow rates

Fig. 3. SEM cross-sectional images of GaN samples at different H₂ carrier gas flow rates

Fig. 4. HRXRD test results of GaN thin films at different H₂ carrier gas flow rates

Fig. 5. TEM cross-sectional image （a）， and corresponding EELS mapping images of Si （b）， Al （c）， Ga （d）， N （e） elements of sample E