Thermal stability of NiTi alloy contacts on n-type liquid encapsulated Czochralski GaAs

The electrical characteristics of NiTi/n-GaAs Schottky barrier diodes annea led at temperatures from 100 to 300 degrees C for 5 min and from 350 to 650 degrees C for 1 min have been investigated as a function of annealing temp erature, with the use of current-voltage (I-V) techniques. The Schottky bar rier height Phi(b) and ideality factor n range from 0.57 eV and 1.06 for as -deposited sample to 0.84 eV and 1.06 for 450 degrees C annealing for 1 min , and 0.80 eV and 1.10 for 500 degrees C. The barrier height for these cont acts increases with increasing annealing temperature. The thermal annealing proceeding has been seen to be useful for improving the electrical charact eristics of NiTi evaporation on Liquid Encapsulated Czochralski (LEC) GaAs. This can be ascribed to thermal stability of the NiTi alloy/n-GaAs SBDs. T he contact properties of the Schottky diodes deteriorated and became nearly ohmic above 650 degrees C for 1 min. (C) 1999 Elsevier Science Ltd. All ri ghts reserved.