Fast Homoepitaxial Growth of 4H-SiC Films on 4° off-Axis Substrates in a SiH₄-C₂H₄-H₂ System

【摘要】 Homoepitaxial growth of 4H-SiC epilayers is conducted in a SiH₄-C₂H₄-H₂ system by low pressure hot-wall vertical chemical vapor deposition（CVD）.Thick epilayers of 45μm are achieved at a high growth rate up to 26μm/h under an optimized growth condition,and are characterized by using a Normaski optical microscope,a scanning electronic microscope（SEM）,an atomic force microscope（AFM）and an x-ray diffractometer（XRD）,indicating good crystalline quality with mirror-like smooth surfaces and an rms roughness of 0.9 nm in a 5μm×5μm area.The dependence of the 4H-SiC growth rate on growth conditions on 4°off-axis 4H-SiC substrates and its mechanism are investigated.It is found that the H₂ flow rate could influence the surface roughness,while good surface morphologies without Si droplets and epitaxial defects such as triangular defects could be obtained by increasing temperature.更多还原

【Abstract】 Homoepitaxial growth of 4H-SiC epilayers is conducted in a SiH₄-C₂H₄-H₂ system by low pressure hot-wall vertical chemical vapor deposition（CVD）.Thick epilayers of 45μm are achieved at a high growth rate up to 26μm/h under an optimized growth condition,and are characterized by using a Normaski optical microscope,a scanning electronic microscope（SEM）,an atomic force microscope（AFM） and an x-ray diffractometer（XRD）,indicating good crystalline quality with mirror-like smooth surfaces and an rms roughness of 0.9nm in a 5μm × 5μm area.The dependence of the 4H-SiC growth rate on growth conditions on 4° off-axis 4H-SiC substrates and its mechanism are investigated.It is found that the H₂ flow rate could influence the surface roughness,while good surface morphologies without Si droplets and epitaxial defects such as triangular defects could be obtained by increasing temperature.更多还原