Investigation on the Rapid Annealing of Ti-Au Composite Electrode on n-Type (111) CdZnTe Crystals

In this paper, the ohmic properties of Ti, Al, and Ti-Au composite electrodes on n-type (111) CdZnTe crystal deposited by vacuum evaporation method were first analyzed, and then the rapid annealing of Ti-Au electrode under Ar atmosphere with different temperature and time was explored. The ohmic property and barrier height were evaluated by current–voltage (I–V) and capacitance-voltage (C–V) measurements, and the adhesion strength of various electrodess to CdZnTe was compared. The Ti-Au electrode on CdZnTe showed the lowest leakage current and barrier height, and the highest adhesion strength among the three kinds of electrodes on (111) CdZnTe crystals. The rapid annealing of Ti-Au electrode under Ar atmosphere was proved to improve its ohmic property and adhesion strength, and the optimal annealing temperature and time were found to be 423 K and 6 min, respectively. The barrier height of the Ti-Au/CdZnTe electrode is 0.801 eV through rapid annealing for 6 min at 423 K annealing temperature, and the adhesion is 1225 MPa, which increases by 50% compared with that without rapid annealing.