One of the most pressing issues in the growth of high quality single crystal Cd0.96Zn0.04Te material, is to achieve homogenization of the high axial variation of Zn concentration, caused by the larger than unity segregation coefficient of Zn in CdTe. This is achieved in our crystals
by thermal annealing of the CdZnTe crystal, which redistributes the as grown Zn distribution by solid state diffusion of Zn (this solid state diffusion of Zn occurs at three stagesduring the growth when the solidified crystal is near to the melting point temperature,
during the post growth annealing of the crystal at a high temperature and
during the cooldown to room temperature) and
by the reduction of Zn segregation during the growth stage by enhanced convective mixing of the melt, through a proper choice of ampoule and furnace dimensions.
By adopting suitable growth parameters and sufficient post growth annealing it has been possible to grow Cd0.96Zn0.04Te crystals, which have nearly 75% of their fraction within 1% Zn concentration variation.
