IN-SITU MEASUREMENT OF GROWTH-RATE BY LASER DIFFRACTION DURING CDTE SINGLE-CRYSTAL GROWTH FROM THE VAPOR-PHASE

The feasibility of a far-field single-slit laser diffraction technique for in-situ growth rate measurements in physical vapour transport was demonstrated with CdTe single crystals. With a special crystal growth ampoule and a furnace with high optical quality windows, a resolution of better than 1 mu m was achieved. It was found that the growth rate of CdTe decreases significantly with growth time. In addition, the dependence of the growth rate on supersaturation (Delta T) was investigated.