| 摘要 |
<p>Provided is a silicon carbide epitaxial wafer, the entire surface of which is free of step bunching. Also provided is a method for manufacturing said silicon carbide epitaxial wafer. The provided method for manufacturing a silicon carbide semiconductor device includes: a step wherein a 4H-SiC single-crystal substrate having an off-axis angle of 5° or less is polished until the lattice disorder layer on the surface of the substrate is 3 nm or less; a step wherein, in a hydrogen atmosphere, the polished substrate is brought to a temperature between 1400°C and 1600°C and the surface of the substrate is cleaned; a step wherein silicon carbide is epitaxially grown on the surface of the cleaned substrate as the amounts of SiH 4 gas and C 3 H 8 gas considered necessary for epitaxially growing silicon carbide are supplied simultaneously at a carbon-to-silicon concentration ratio between 0.7 and 1.2 to 1; and a step wherein the supply of SiH 4 gas and the supply of C 3 H 8 gas are cut off simultaneously, the substrate temperature is maintained until the SiH 4 gas and the C 3 H 8 gas are evacuated, and then the temperature is decreased.</p> |
