Nano-scale patterning of metal surfaces by adsorption and reaction

Nano-scale patterning of the metal surfaces was attained by the adsorption and the reaction of metal atoms. Growth of metal islands on the metal surfaces was markedly influenced by preparing the surface with preadsorption andror by the reconstruction. Adsorption of oxygen on Cu 100. form randomly coalesced nano-size c 2=2.-O which undergoes the 2ʹ2 =ʹ2.R458 reconstruction with increasing the oxygen coverage. In contrast, N-atoms on Cu 100.make well ordered array of squared c 2=2.-N patches of ca. 50 A°2. Cu atoms deposited on the nano-size c 2=2.-O Cu 100.form one atomic height rectangular Cu islands but Ni atoms undergo no orientational growth of Ni islands. Ni atoms deposited on the 2ʹ2 =ʹ2.R458-O Cu 100. surface, however, gave an extremely anisotropic growth of Ni-wire. In contrast, when Ni atom was deposited on a Cu 100.surface having a super-grid like pattern made by the boundaries of squared c 2=2.-N patches, one atomic height Ni islands grew at the crossings of the super-grid. These phenomena are distinctive from the chemical reaction of surface atoms which provides various quasi-compounds. The reaction of Cu with –Ag–O–.strings on Ag 110.provided a new quasi-compound of –Cu–O–.on Ag 110., which undergoes a reversible reaction of –Cu–O–.¡ Cu.6qO2. In addition, the –Ag–O–.strings on Ag 110.undergo selective photo-erasing. These results suggest that chemical reaction is a promising tool for making atomic-scale pattern on the surface. q1998 Elsevier Science B.V. All rights reserved.