Fermi level movement fornhyphen; andphyphen;GaAs interfaces: Effects of temperature and dopant concentration

摘要

Photoemission studies demonstrate that temperature and dopant concentration dependent movement of the surface Fermi level is controlled by coupling between adatomhyphen;induced and bulk states. At a low temperature for lightly dopednhyphen; orphyphen;GaAs, initial band bending inhibits tunneling andEFremains near the band edges until the onset of metallicity. For heavy doping, greater band bending reflects a thinner depletion region. Thermal cycling for 20le;Tle;300 K for low coverages demonstrates that band bending is reversible.