Amorphous semiconductor has a wide band tail and abundant metastable electrons, which is conducive to promoting the interfacial charge transfer between the substrate and adsorbed molecules, thus amplifying the molecular polarizability and realizing surface-enhanced Raman scattering (SERS). We designed a series of substrate materials with high SERS properties, such as amorphous nanocages, nanosheets and noble metal-amorphous semiconductor composite structures, and explored their applications in cancer diagnosis, environmental monitoring, food safety and other fields.