A fully plasma-based technique of generating ultrafine (sub-10-nm) nanocrystalline silver particulates on wide band gap and chemically inert hexagonal aluminum nitride nanorod templates has been demonstrated. These specially prepared substrates are ready to use for molecular sensing by room-temperature surface-enhanced Raman scattering. An enhancement factor of 2 x 106 was observed for micromolar solutions of Rhodamine 6G.