A method of fabricating a nanowire sensor device structure includes preparing a substrate, having a silicon base layer, a buried oxide layer in the silicon base layer, a top silicon layer on the buried oxide layer, and a doped well in the silicon base layer; forming a silicon island from the top silicon layer; etching the buried oxide layer to undercut the silicon island in some instances; depositing a seed layer of polycrystalline ZnO over the silicon island, the buried oxide layer, the doped well and the silicon base layer; selectively removing the polycrystalline ZnO from the silicon island; growing and structuring ZnO nanostructures on the seed layer of ZnO; treating the ZnO nanostructures to sensitize the ZnO nanostructures to a desired application; depositing a layer of insulating material; patterning and etching the insulating material; and metallizing the nanowire device structure.