Since the majority of bulk crystal growth methods involves melt freezing, the knowledge of the molten state properties is one of the most important parameter coming into the improvement of the growing crystal and method. It is well known that melting of covalent semiconductor destroys covalent bonds and induces metallic type liquid. The phenomenological model of viscosity developed by Kim and Chair has demonstrated very good agreement for normal liquid, helium or monoatomic metals. In this paper, we propose to use it in the case of semiconductor melts.