Platinum/erbium disilicide nanowire arrays on Si(001)

Self-assembled ErSi_2-x nanowires were grown on Si(001) substrates with average nanowire width of 2.8 nm. Submonolayer coverage of platinum was deposited postgrowth. Scanning tunneling microscopy showed that platinum preferentially deposited on the nanowire surface versus the Si surface. Reactive ion etching of ErSi_2-x nanowires with and without platinum on the surface demonstrated that platinum acted as a more resistant etch mask. Etching platinum coated nanowires with lower platinum coverage produced linear arrays of quantum dots with a diameter of approximately the pre-etched nanowire width. The platinum layer was shown to passivate the highly reactive rare earth disilicide surface.