No abstract

Epitaxial Pt films with (111) and (100) orientations were grown on Y 2 O 3 -stabilized ZrO 2 (YSZ)-covered (100)Si substrates by RF sputtering. (111)Pt films were epitaxially grown on (100)YSZ==(100)Si substrates at 580 and 680 C, but competitive crystal orientations of (111) and (100) at 780 C. In contrast, a (100)-oriented epitaxial Pt film was grown at 550 C on a (100)YSZ==(100)Si substrate with a (100)-oriented epitaxial (100)Ir buffer layer. This orientational control of epitaxial Pt films enables the epitaxial growth of perovskite layers with different orientations on thermally and chemically stable Pt bottom electrodes grown on (100)Si substrates.

No abstract

We have already developed a uniform silicon-based two-dimensional quantum dot superlattice (2D QDSL) (i.e., 2D array of Si nanodisks) on the x–y plane with high-density nanodisks (NDs) and controllable size and spacing between NDs. To integrate more nanodisks in the third dimension (z-axis), a new stacked nanodisk (S-ND) has been developed by using thin film deposition, bio-template and advanced alternate etching. The S-ND structure comprises of two NDs connected vertically by coupling a tunnel junction (TJ). The scanning transmission electron microscopy image clearly revealed the stacked structure. The quantum confinement of S-ND was confirmed by observing the Coulomb staircase at room temperature. Tunneling current could be controlled by changing TJ thickness. By simply changing the ND thickness, band gap energy (E g) could be controlled. These characteristics of the quantum effect and E g play important roles in QDSL solar cells.

A compact, low-height prototype of a six-axis precise positioning stage for microfabrication h a s been developed. X and Y stage positioning requires nanometer positioning resolution and robustness against atmospheric turbulence. The stiffness and dead play of the traveling mechanism were improved by using rolling contact guides, and the positioning resolution was improved by using a iriction drive mechanism. Anaiog signais from a n opticai h e a r scaie are influenced little by atmospheric turbulence. Using these advantages of the optical linear scale and with a newlv develoDed Dositioning algorithm. one-nanometer resolution was obtained.