Method for manufacturing silicon carbide semiconductor device

Abstract

Gas containing Si, gas containing C and gas containing Cl are introduced into a reacting furnace. SiC epitaxial film is grown on the surface of a 4H—SiC substrate by CVD in a gas atmosphere including raw material gas, additive gas, doping gas and carrier gas. The amount of the gas containing Cl relative to the gas containing Si in the gas atmosphere is reduced gradually. At the start of growth, the number of Cl atoms in the gas containing Cl is three times as large as the number of Si atoms in the gas containing Si. The number of Cl atoms in the gas containing Cl relative to the number of Si atoms in the gas containing Si in the gas atmosphere is reduced at a rate of 0.5%/min to 1.0%/min. The method grows silicon carbide semiconductor film at a high rate.

Dependencies are inferred from the claim text.