Effects of annealing on the properties of Au–Cd0.9Zn0.1Te contacts

Au–Cd0.9Zn0.1Te contacts were annealed for 10 min at 100, 200 and 300 °C, respectively. The effects of annealing have been analyzed with photoluminescence (PL) spectra, leakage current-bias voltage (I–V) characteristic and leakage current–time (I–t) characteristic. PL spectra indicate that there are more Au-related complexes and Cd vacancies (Zn vacancies) produced in Au–Cd0.9Zn0.1Te contacts during the annealing. These complexes and vacancies are responsible for the decrease of leakage current, which is revealed by I–V measurement, because they can trap free charge and improve the recombination rate of charge effectively. The I–V measurement also shows that the ohmic characteristic of Au–Cd0.9Zn0.1Te contacts is improved obviously by the annealing at 100 and 200 °C and deteriorated seriously by the annealing at 300 °C. In addition, I–t curves suggest that annealing can improve the stability of leakage current remarkably.