With abandoning the use of traditional diamond particles with slightly higher hardness to achieve grindingthinning, we first use an electrochemical process to selectively etch silicon atoms in the crystal structure to weaken the strength of the SiC substrate by sponge-like structure formation. The sponge-like structure at a certain depth can be easily removed by general soft abrasives therefore, the thinning can be stopped at the solid/sponge boundary to achieve an accuraterapid thinning result on silicon carbide.

Our technology has developed electrochemical etching systems mainly based on hydrofluoric acid to weaken the strength of semiconductor materials in a specific region. According to Faraday’s law, the thickness to be removed can be precisely controlled with the amount of input electrons. The Si atoms are selectively removed by anodization, leaving a carbon atom skeleton, thus forming a sponge structure, so the desired part can be removed by ordinary abrasives. Through XRD diffractionlattice spacing detection, it is determined that the suspended particles in the electrolyte are fluorinated graphene. The technology can not only avoid high residual stresses with rapid thinning, but the value of waste liquid is high for recycling.

To develop power semiconductor components based on the third semiconductor as the substrate material, manufacturers have begun to grow silicon carbide ingotsproduce cutting, grindingpolishing processes. The shortage of SiC substrates is most acute in the electric vehicle industry, which uses the largest number of power semiconductors. The famous market research expert Yole even predicts that the production of electric vehicles will reach 50 million in 2027. Hence, according to estimates, two cars consume a six-inch silicon carbide wafer,the demand is as high as 25 million