Structure of ion-implanted and annealed Hg1−xCdxTe

Abstract

The structural and compositional changes in ion‐implanted and annealed Hg_1−xCd_xTe (x=0.21; 0.29) were studied by means of ion‐beam probing techniques. Rutherford backscattering (RBS) and particle‐induced x‐ray (PIXE) experiments were carried out under channeling the nonchanneling conditions. The following results were found. (i) The damage caused by room‐temperature implantation of a variety of ions (Al, P, Ar, In, Hg) reaches saturation when an energy density of 2–4×10²⁴ eV/cm³ goes into nuclear collisions. (ii) The damage profile for light ion implantation (150‐keV, P, Ar) is more shallow than the implant range, while for heavy implants (300‐keV, In, Hg) it extends substantially deeper than the range. (iii) The damage consists of extended defects, probably stacking faults. The results of furnace, Q‐switched ruby, and cw CO₂ laser annealing were investigated. Best annealing was obtained when the implanted surface was irradiated with photons from a cw CO₂ laser for 0.3 sec at a power of 250 W/cm². Under such conditions the crystallinity is restored and no changes in stoichiometry are evident. The theoretical considerations for the choice of RBS or PIXE analyses for compound crystals are reviewed.