Method for simultaneously producing multiple sheets of sic single crystal substrate

A method for simultaneously manufacturing multiple SiC single crystal substrates, the method comprising:

• preparing a plurality of containers;
• placing, in each of the plurality of containers, an SiC single crystal serving as a seed crystal and an SiC mixed powder comprising SiC powder and a liquid phase sintering aid so as to form an SiC mixed powder layer in which the SiC mixed powder is in contact with at least one surface of the SiC single crystal, wherein the liquid phase sintering aid comprises an oxide;
• arranging the plurality of containers in a firing furnace so as to be aligned horizontally and/or vertically;
• and
• heating the inside of the firing furnace to form a temperature gradient in which the temperature increases or decreases from an upper part to a lower part of the firing furnace, and subjecting the plurality of containers containing the seed crystal and the SiC mixed powder to heat treatment at an average furnace temperature of 2,240 to 2,560° C., whereby an SiC single crystal is grown on the seed crystal.