Gold/Ga0.85Al0.15Sb schottky diodes

Gold on n‐type Ga0.85Al0.15Sb devices were prepared and characterized. Current versus voltage (I‐V) and capacitance versus voltage (C‐V) measurements are discussed following the classical models of thermionic field emission and metal‐insulator‐semiconductor devices. The agreement between experimental I‐V results and thermionic field emission model is obtained for a barrier height value of 0.73 eV but the parameter N/m*e (N: carrier concentration; m*: effective mass; e: dielectric constant) involved in this model is ten times higher than the expected one, deduced from the doping level in the layer and from m* and e values in Ga0.85Al0.15Sb. In the case of the metal‐insulator‐semiconductor model, the comparison between the predicted and the experimental values of both the ideality coefficient n and the threshold V0 of C−2 versus reverse bias, allows to deduce the thickness of the surface insulating film δ≂45 A. As generally observed, the barrier height χ presented to electrons by the insulating layer is sma...