In this study, we used a horizontal hot-wall CVD epitaxy apparatus to grow epitaxial layers on 4° off-axis 4H-SiC substrates. Epitaxial films were grown by adjusting the flow rate of the source gas at different levels. With an increase in the source gas flow rate, a notable transition in the crystalline structure of the epitaxial layer was observed, gradually shifting from 4H-SiC to 3C-SiC. Furthermore, the quality of the epitaxial layer correspondingly exhibited degradation. Specifically, for epitaxial films grown under moderate gas flow rates, the central region demonstrated a crystalline structure of 4H-SiC, while the outer ring region exhibited a crystalline structure of 3C-SiC. Using a scanning electron microscope (SEM) to observe the transition zone of the two regions, a region of 3C/4H overlapping growth below it was found. Bright areas corresponded to 3C, while dark areas corresponded to 4H, as confirmed by Raman spectroscopy and other SEM images. The growth interfaces of the two crystal types were clearly discernible and relatively compact. Furthermore, the growth angles of the two crystal types and their correlation with the cutting direction strongly suggest that this overlap is related to the formation of micro-nano steps on the substrate surface.

The growth of 6-inch In0.485Ga0.515P has been examined in this study. The effects of growth temperature, the V/III ratio, and the H2 total flow on solid composition, growth rate, and crystal quality have been systematically investigated and discussed. Additionally, the effect of growth conditions on doping efficiency has been investigated. Finally, the relationship between electrical uniformity, optical uniformity, and the growth conditions of the 6-in epitaxial layer is discussed. At a growth temperature of 600 °C and a V/III of 250, a high uniformity 6-in InGaP epitaxial layer with an electrical uniformity of 0.33% and optical uniformity of 0.03% was produced. InGaP was grown by the metal-organic chemical vapor deposition method in an Aixtron 2800G4 reactor. High resolution X-ray diffraction (HRXRD), photoluminescence (PL), sheet resistance, electrochemical capacitance-voltage (ECV), and the Hall effect were used to characterize the characteristics of InGaP epitaxial layers.