Effect of thermal annealing on the structural and electrical properties of HgTerCdTe superlattices

Rapid thermal annealing effects on the structural and electrical properties of the HgTerCdTe superlattices grown on the Cd0.96Zn0.04Te substrates by molecular beam epitaxy have been investigated by double-crystal X-ray rocking curve DCRC. and Van der Pauw Hall effect measurements. The sharp satellite peaks of the DCRC spectra measured on as-grown HgTerCdTe superlattices show a periodic arrangement of the superlattice with high-quality interfaces. As the annealing time increases, the peak intensities corresponding to ms"1 of the DCRC spectra decrease dramatically. The average diffusion coefficient of the Hg in a HgTerCdTe superlattice annealed at 2208C is approximately 10y18 cm2rs. After annealing, the results of the Hall effect measurements show that the carrier concentration and the mobility of the HgTerCdTe superlattice are changed resulting from the formation of Hg vacancies and that the n-type HgTerCdTe superlattice has converted to the p-type HgTerCdTe superlattice with a high carrier concentration. These results indicate that the heterointerface of the HgTerCdTe superlattice annealed at 2208C is significantly intermixed and that the monotonous variation of the intensity for the satellite peak in annealed HgTerCdTe superlattice is attributed to a linear diffusion behavior. q1999 Elsevier Science B.V. All rights reserved