Self-organized monocrystalline Au nanoparticles with potential applications in plasmonics are grown in a SrTiO$_3$ matrix by a novel two-step deposition process. The crystalline preferred orientation of these Au nanoparticles is investigated by synchrotron hard x-ray diffraction. Nanoparticles preferentially align with the (111) direction along the substrate normal (001), whereas two in-plane orientations are found with $[110]_{ SrTiO_3} \: || \: [110]_{ Au}$ and $[100]_{ SrTiO_3} \: || \: [110]_{ Au}$. Additionally, a smaller diffraction signal from nanoparticles with the (001) direction parallel to the substrate normal (001) is observed; once again, two in-plane orientations are found, with $[100]_{ SrTiO_3} \: || \: [100]_{ Au}$ and $[100]_{ SrTiO_3} \: || \: [110]_{ Au}$. The populations of the two in-plane orientations are found to depend on the thickness of the gold film deposited in the first step of the growth.
Categories: cond-mat.mes-hall cond-mat.mtrl-sci physics.optics