Rapid thermal annealing effects on electrical and structural properties of Pd/Au Schottky contacts to n‐type InP(111)

The effects of rapid thermal annealing on the electrical and structural properties of Pd/Au Schottky contacts to n‐type InP(111) have been investigated by current–voltage ( I – V ), capacitance–voltage ( C – V ) and X‐ray diffraction (XRD) measurements. The barrier height of the as‐deposited Pd/Au Schottky contact was found to be 0.46 eV ( I – V ) and 0.70 eV ( C – V ) respectively. It is observed that the Schottky barrier height increases with annealing temperature and found maximum values of 0.51 eV ( I – V ) and 0.92 eV ( C – V ) annealed at 400 °C for 1 min in the nitrogen atmosphere. However, after annealing the sample at 500 °C resulted in the decrease of barrier height and values are 0.40 eV ( I – V ) and 0.60 eV ( C – V ). The AFM results showed that the surface morphology of the contact annealed at 500 °C is fairly smooth with a RMS roughness 1.9 nm. Based on the XRD results, the formation of indium phases at the Pd/Au/n‐InP interface could be the reason for the increase in the Schottky barrier height at 400 °C. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)