We report the fabrication of nanopores in a silicon oxynitride (SiON) membrane by heating a silicon rich-silicon nitride (SiRN) membrane with a gold nanoparticle array deposited on its surface. The gold nanoparticle array was realized by photolithography and the membrane by wet-etching. The entire process is wafer scale. Nanopore through-holes of an average diameter of 150 nm were produced in a ~22 nm thick membrane. Membranes and nanopores were characterized by atomic force microscopy, scanning transmission electron microscopy, and x-ray photo-electron spectrocopy.