SiC power device is becoming crucial in new energy industry, especially in driving the BEV car to penetrate the market. However, comparing with Si devices, SiC devices are prevailing their applications, since making SiC devices reliable is still challenging. The reliability issues might arise from substrates, epi, processing, assembly, even the final test and application. In this presentation, the defects from different processing stages are sampled, and their impacts on device reliability are outlined. It can be seen that effective tools and more reliable data are needed for screening those flawed devices. In YASC, we are introducing new tools, accumulating data, and know-how to make the SiC device reliable and robust.