Electronic structure of K/Si(111) interfaces

Photoemission studies of the K/Si(111)7×7 and K/Si(111)(√3×√3)R30°‐B interfaces show that both interfaces are semiconducting at room temperature saturation coverage. At both types of interfaces, a dispersionless K‐induced surface state is observed below the Fermi level. We argue that these interfaces are correlated systems. We provide conclusive evidence that the onset of metallization and long‐range conductivity occurs during the development of the second and third layers at cryogenic temperatures.