Growth of arsenic-doped cadmium telluride epilayers by metalorganic chemical vapor deposition

Abstract

We have studied arsenic incorporation from tris(dimethylamino)arsine into epitaxial CdTe layers in a metalorganic chemical vapor deposition (MOCVD) process. Arsenic incorporation into the layers has been shown to depend on the crystallographic orientation of their growth. Incorporation effectiveness increases in the order (111)B < (211)B < (100) < (310) < (211)A. Arsenic concentration in the CdTe layers is proportional to the tris(dimethylamino)arsine flow rate to the power 3/2. The dependence of arsenic incorporation on the ratio of the metalorganic tellurium and cadmium precursors in the vapor phase suggests that arsenic is incorporated predominantly into the anion sublattice. The maximum concentration of free charge carriers, p₂₉₅ = (1–2) × 10¹⁷ cm^–3, was observed after annealing of the arsenic-doped CdTe layers in an argon atmosphere.