Post-growth, In doping of CdTe single crystals via vapor phase

We have developed a new, efficient method to dope bulk single crystals of C dTe by In, via gas phase diffusion, using In4Te3 as the source. Doping was carried out on crystals of very high resistivity (>5 M Omega cm), following annealing in the temperature range of 350-1000 degrees C. Resulting crysta ls showed n-type conductivity with a free carrier concentration in the rang e: of 10(15)-10(18) cm(-3) and carrier mobility of 100-750 cm(2)/(V s), dep ending on the annealing temperature and time, and on the cooling conditions . Incorporation of In was found to be a function of annealing time and temp erature only. Up to 650 degrees C, the In and the free electron concentrati ons are roughly the same. (C) 1999 Elsevier Science B.V. All rights reserve d.