TOPOGRAPHIC STUDY BY SCANNING-TUNNELING-MICROSCOPY OF A 2-DIMENSIONALGRAPHITE FILM ON RE(10(1)OVER-BAR0)

Two-dimensional graphite films on Re(10 (1) over bar 0) were produced in ultrahigh vacuum by adsorption of benzene vapor on the metal heated to T = 1800 K. High-resolution Auger spectroscopy used for the film c haracterization showed the film indeed to have graphitic structure and monolayer thickness. The surface topography was studied in air by sca nning-tunneling microscopy. The monolayer thickness was confirmed, and it was shown that a two-dimensional graphite film has a complex topog raphy featuring numerous hillocks with linear dimensions of similar to 3000 Angstrom and height differences of similar to 300 Angstrom, whil e retaining graphitic structure on the atomic scale. The lack of plana rity of such a film at room temperature is considered to be due to def ormation occurring under cooling from the temperature of formation dow n to 300 K, which is caused by the difference in thermal expansion coe fficients between the graphite sheet and rhenium. (C) 1998 American In stitute of Physics. [S1063-7834(98)03608-9].