INVESTIGATION OF STRUCTURES OF TETRAKIS(THIADIAZOLE)PORPHYRAZINE ON GOLD SUBSTRATE USING UHV-STM.

TERUI, TOSHIFUMI; MASHIKO, SHINRO; SUZUKI, YOSUKE; FUJIMORI, MASATO; AWAGA, KUNIO

It has been proposed that a bottom–up approach is necessary to make nanometer-scale devices. To improve the bottom–up approach, we need to observe and evaluate the structure and array of molecules on a substrate. Generally, the conformation of molecules at interfaces is critical in molecular devices. Numerous studies of phthalocyanine compounds have been done because of their high potential for applications in electro-optical and magnetic devices. Tetrakis(thiadiazole)porphyrazine (TTDPzH2) is one of the molecules that has been synthesized to control intermolecular interactions. X-ray crystal analysis revealed a 2D close packing structure. However, the details of intermolecular interaction and molecule–substrate interaction in thin films are not completely understood. We have observed the structure and arrangement of molecules that reflect their structural characteristics by using a scanning tunneling microscope (STM). Molecules were deposited on gold substrates to a sub-monolayer thickness. STM images of monolayer thin films showed differences in the crystal structure between as-deposited and post-annealed films. STM images of sub-monolayer films showed small dots that are consistent with TTDPzH2 molecule and cluster structures on the substrate terrace.

THIADIAZOLES; NANOSTRUCTURED materials; SCANNING tunneling microscopy; SEMICONDUCTOR industry; PHOTOLITHOGRAPHY; SCANNING probe microscopy

International Journal of Nanoscience, 2006, Vol 5, Issue 6, p889

0219-581X

Academic Journal

10.1142/S0219581X06005327