Measurement of the diffusivity of CdTe in liquid Te at crystal growth temperatures

The diffusivity of CdTe in tellurium-rich liquid solution was measured by dissolving solid samples at temperatures applicable to THM crystal growth. We calculated the resulting diffusion coefficients to be 0.008mm2/s at 850 °C and 0.009mm2/s at 900 °C. The CdTe was dissolved under isothermal conditions in 7 mm diameter quartz tubes for 45 min, 90 min and 180 min. The diffusivity was calculated from the distance travelled by the dissolution interface using a 1D transport model. Measurement of the solution composition by EDS confirms that the experiments were diffusion-dominated, and the calculated diffusivities match those predicted elsewhere ab initio for similar conditions.