Fermi Level Movement for n- and p-GaAs Interfaces: Effects of Temperature and Dopant Concentration

S.G. ANDERSON; C.M. ALDAO; G.D. WADDILL; I.M. VITOMIROV; C. CAPASSO; J.H. WEAVER

APPLIED PHYSICS LETTERS

AMER INST PHYSICS

Lugar: New York; Año: 1989 vol. 55 p. 2547 - 2549

0003-6951

Photoemission studies demonstrate that temperature and dopant concentration dependent movement of the surface Fermi level is controlled by coupling between adatom-induced and bulk states. At a low temperature for lightly doped n- or p-GaAs, initial band bending inhibits tunneling and EF remains near the band edges until the onset ofmetaHicity. For heavy doping, greater band bending reflects a thinner depletion region. Thermal cycling for 20< T < 300 K for low coverages demonstmtes that band bending is reversible.