Ohmic Contact of Au/Mo on Hg1−x Cd x Te

Abstract

The contact resistance between Au/Mo and HgCdTe was investigated. The influence of thermal annealing on metal–semiconductor contact on short and middle-wavelength HgCdTe is also discussed in this paper. The specific contact resistance ρc (300 K, 80 K) of Au/Mo/HgCdTe was measured by the transmission line method. Good ohmic contacts can be formed with Au/Mo on long-wavelength infrared p-HgCdTe (x = 0.23) with a low specific contact resistivity of 3.78E−04 Ωcm2 measured at 80 K. For the mid-wavelength infrared p-HgCdTe (x = 0.30), the metal–semiconductor contact is ohmic, and the minimum specific contact resistivity of 7.40E−04 Ωcm2 is obtained after annealing at 120°C/10 min. The as-deposited contact between Au/Mo and the short-wavelength infrared HgCdTe (x = 0.47) shows non-ohmic behavior. After annealing at 120°C/5 min, although the contact behavior is still a Schottky contact, the contact resistance decreases. For the n-HgCdTe (x = 0.27), the metal–semiconductor contact is ohmic with a specific contact resistivity of 5.70E−04 Ωcm2 at 80 K.