Analysis of Carrier Species in Arsenic-Implanted P- and N-Type Hg0.7Cd0.3Te

Carrier species in arsenic-implanted p? and n?type Hg0.7Cd0.3Te films grown by molecular-beam epitaxy were investigated with the use of the Hall-effect studies and mobility spectrum analysis. The implantation was performed with ion energy 190 or 350 keV and ion fluence ranging from 1012 to 1015 cm? 2. A substantial difference between carrier species in Hg0.7Cd0.3Te and Hg0.8Cd0.2Te films subjected to arsenic implantation and postimplantation activation annealing was established. In particular, arsenic implantation in p?type Hg0.7Cd0.3Te in most cases lead to the formation of n+?p? (not n+?n?p?) structures, and in n?type Hg0.7Cd0.3Te films postimplantation activation annealing lead to modification of the electrical parameters of the n?type ?base?, in contrast to Hg0.8Cd0.2Te material studied earlier. The difference in carrier species formed in arsenic-implanted Hg0.7Cd0.3Te and Hg0.8Cd0.2Te films was tentatively explained by different background impurity concentrations in the films with different chemical composition.