Dependence of thermal annealing on the density distribution of interface states in Tirn-GaAs Te/Schottky diodes

The Tirn-GaAs Te.Schottky barrier diodes have been annealed in the temperature range 200–4008C with steps of 1008C for 5 min. The barrier height value has increased with increasing annealing temperature. This increase has been attributed to that the annealing removes the passivation effect of the native oxide layer and reactivates the surface defects which are responsible for the Fermi level pinning. The value of equilibrium interface charge density Qss 0. has increased with increasing annealing temperature. It has been found that the experimental density distribution curves of the interface states and the values of equilibrium interface charge density Qss 0. has confirmed this interpretation. The results indicate that the negative equilibrium interface charge is responsible for the actual equilibrium barrier height value. q1999 Elsevier Science B.V. All rights reserved