摘要
It appears that CdTe cannot be doped p-type with a carrier concentration higher than 10 18 cm -3 by near equilibrium processes. In a previous study by our group, a hole concentration of 5×10 19 cm -3 was obtained by phosphorus implantation and pulse electron beam (PEB) annealing. In this paper, an analysis is extended to explain the experimental data of the different annealing processes. The profiles of implantation-induced defects as well as the temperature distribution of PEB annealing and the phosphorus redistribution after the annealing process are calculated. The results show a strong dependence of the measured hole concentrations on the redistributed phosphorus atoms in CdTe after PEB annealing, while the implantation-induced point defects greatly affect the resultant electrical characteristics in thermally annealed samples. A logical explanation for these two cases is that the p-type conduction in the thermally annealed CdTe is compensated by cadmium vacancies, and is promoted by phosphorus interstitials, while in the PEB annealed samples phosphorus at substituted tellurium sites are easily formed due to the melting effects. © 1988.