Direct comparison of the results of arsenic ion implantation in n– and p–type Hg0.8Cd0.2Te

Abstract

Optical reflectance in the visible wavelength range, transmission electron microscopy, and the Hall-effect measurements with mobility spectrum analysis have been used for the direct comparison of the results of arsenic ion implantation in samples with n– and p–type conductivity fabricated on the basis of a Hg1-xCdxTe film with x = 0.22 grown by molecular beam epitaxy on a Si substrate. Optical reflectance studies showed that the effect of ion implantation on the properties of the surface was very similar in n– and p–type material. Transmission electron microscopy showed that defect patterns were also similar in n– and p–type samples in terms of the thicknesses of implantation-damaged layers and types of defects formed. Electrical studies demonstrated that low- and mid-mobility electrons induced by the implantation in n– and p–type material had similar average concentration and mobility. It was concluded that the nature of donor defects that produced these electrons was the same in n– and p–type HgCdTe, and it was suggested that the defects in question were interstitial mercury atoms captured by dislocation loops and by quasi-point defects formed as a result of implantation.