Local hydride formation of the Si(111)-(7×7) surface by hydrogen atoms deposited from a scanning tunneling microscope tip

The Si(111)-(7×7) surface can be locally hydrized at the nanometer scale by depositing H atoms from the tip of a scanning tunneling microscope. The H atoms to be deposited are continuously supplied to the tip made of Pt (20% Ir) from an ambient ${\mathrm{H}}_2$ molecule gas through dissociative adsorption (${\mathrm{H}}_2$→2H) and are deposited onto the Si(111)-(7×7) sample surface one by one by field evaporation; although the ambient ${\mathrm{H}}_2$ molecules are not adsorbed on the Si(111)-(7×7) surface, the H atoms from the tip are adsorbed on the surface.