Electrical Characterization of GaAs Epitaxial Layers Grown by CSVT from Zn‐doped GaAs Sources

epitaxial layers have been grown by close‐spaced vapor transport (CSVT) from various p‐type Zn doped sources, using as transporting agent. The doping impurity concentrations in the sources were in the 10 16 , 10 18 , 10 19 , or 10 20 cm −3 ranges. Heavily compensated n‐type epitaxial layers were obtained with sources characterized by an acceptor concentration in the 10 16 –10 18 range, while p‐type layers were obtained with sources having Zn concentrations equal or greater than 10 19 cm −3 . About 1% of the Zn present in the source is found to be electrically active in the epitaxial layer. With the help of a diffusion control model based only on thermodynamic analysis, it is possible to demonstrate that Zn is transported as . Using the same model, it is also shown that Te, a n‐type doping impurity characterized in CSVT by a transfer coefficient of unity, is transported as under the same growth conditions.