The formation of inhomogeneities in CdxHg1-xTe alloys upon post-growth cooling or upon low-temperature annealing was simulated numerically. The mechanism of the formation of inhomogeneities was based upon the diffusion instability in a system involving Hg atoms located at lattice sites, interstitial Hg atoms, and cation vacancies. It was revealed that, upon prolonged annealing of the CdxHg1-xTe alloys with a Cd content of x = 0.2 at about 200C, the concentrations of Hg atoms at lattice sites, interstitial Hg atoms and vacancies were characterized by an inhomogeneous nearly-periodic distribution arising from a small fluctuation when the initial equilibrium concentration of interstitial Hg atoms exceeded a threshold value (about 3 x 1017/cm3). The spatial and time scales of the concentration distribution were determined mainly by the equilibrium concentration of vacancies and did not depend upon the type of fluctuation involved. The spatial period of the concentration distribution increased linearly from 0.01 to 3.00μm as the equilibrium concentration of vacancies changed from 1019 to 1014/cm3. At lower concentrations of vacancies, the periodic structure formed for a considerably longer time.

Simulation of Diffusion Instability of a Mercury Atomic Distribution in the Cadmium-Mercury-Tellurium Alloy. A.S.Vasin, M.I.Vasilevsky: Physics of the Solid State, 2006, 48[1], 37-41