ELECTRICAL-PROPERTIES OF ION-IMPLANTED LAYERS IN HG0.79CD0.21TE

The influence of ion-irradiation damage on the electrical properties of Hg0.79Cd0.21Te has been investigated. A large damage-induced n-type conductivity with sheet carrier concentration up to approximately 1014 cm-2 and sheet resistance up to 10 Ω/square at 77 K was found for doses of 1×1015 ions/cm2 at 150 keV. The observed n-type conductivity is produced by various implanted ions regardless of whether they are donors or acceptors. The implanted n-type layer maintains its properties when subjected to temperatures as high as 120 °C. The damage is slightly annealed for this moderate treatment: the conductivity increases slightly, the sheet electron concentration decreases, and the effective mobility increases. The results also show that the implanted layer can be utilized for surface passivation of n-type photoconductors and for making Ohmic contacts to n-type material.