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 de pendence of the growth rate on supersaturation (Delta T) was investiga ted.