Silicon carbide PiN device ohmic contact method

The invention belongs to the field of PiN devices, and particularly relates to a silicon carbide PiN device ohmic contact method. The method comprises the following steps that a) a silicon carbide PiN base body is prepared; b) an amorphous silicon layer is deposited on the surface of the P-type SiC epitaxial layer of the silicon carbide PiN base body; c) a metal layer is respectively deposited on the surface, on which the amorphous silicon layer is deposited, of the SiC substrate of the silicon carbide PiN base body and the surface of the amorphous silicon layer; and d) annealing processing is performed on the silicon carbide PiN base body on which the metal layer is deposited so that a silicon carbide PiN device with formation of ohmic contact is obtained, wherein annealing processing includes a first temperature rising period, a first heat preservation period, a second temperature rising period and a second heat preservation period, and temperature of the first heat preservation period and the second heat preservation period is respectively 450-550 DEG C and 970-1020 DEG C. According to the method, P-type ohmic contact and N-type ohmic contact can be formed on the silicon carbide PiN base body on which the metal layer is deposited through one time of annealing process.