Abstract:
Well-aligned IrO2 nanocrystals (NCs) have been grown on sapphire (SA) substrates by rf magnetron sputtering using Ir metal target. The surface morphology and structural properties of the as-deposited NCs were characterized using field-emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD). FESEM micrographs reveal that vertically aligned NCs were grown on SA (100), while the NCs on SA (012) and (110) show single and double aligned-directions, respectively, with a tilt angle of ~35º from the normal to the substrates. The XRD results indicate that the IrO2 NCs are (002) oriented on SA (100), and (101) oriented on SA (012) and (110) substrates. A strong substrate effect on the alignment of the IrO2 NCs growth has been demonstrated and discussed.