Having been exposed to hydrogen plasma, Tehyphen;doped GaAs wafers were deposited with metal Ti, to form Ti/nhyphen;GaAs Schottky barrier diodes (SBD). It was found that due to hydrogenation the Schottky barrier height (SBH) of the SBD decreases from 0.76 to 0.58 eV and the effective Richardson constantAast;ast; decreases from 11 to 0.03 A/cm2/K2. Annealing the hydrogenated SBD at different reverse biases at 100thinsp;deg;C produces SBHs that have a onehyphen;tohyphen;one correlation with the biases of reversehyphen;bias annealing (RBA), i.e., the SBH can be controlled, within the range 0.58ndash;0.74 eV, by the bias of RBA. When the reverse bias is equal to or larger than 3 V, the SBH and the effective Richardson constant of the hydrogenated SBDs after RBA are very near to those of SBDs without hydrogenation. This means that a RBA with a bias higher than a critical value, 3 V in our case, can remove the effects of hydrogenation, but if the SBD is annealed again without a bias at 100thinsp;deg;C for 1 h or more, its SBH and effective Richardson constant recover their hydrogenated values. The main experimental facts can be explained qualitatively by a simple theoretical model.
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