Method for removing carbon precipitation after laser annealing of back surface of SiC device

The invention provides a method for removing carbon precipitation after back laser annealing of a SiC device, and the method comprises the steps: the SiC device comprises a SiC chip and an alloy layer disposed on the chip, the SiC chip is provided with a back surface and a front surface opposite to the back surface, and the back surface is subjected to metal sputtering treatment and laser annealing treatment, so that the alloy layer is formed on the back surface; arranging a protective film on the front surface of the SiC chip; the alloy layer is subjected to oxygen plasma treatment, oxygen reacts with carbon separated out of the alloy layer to remove carbon separated out of the alloy layer, and the SiC device with the separated-out carbon removed is obtained. In the invention, the front surface of the SiC device is protected by using the protective film, then oxygen plasma is released through oxygen plasma treatment, and the oxygen plasma reacts with carbon on the alloy layer (a gas compound of carbon is gen