A Study of Arsenic Dopant Concentration and Activity as a Function of Growth Conditions in Polycrystalline MOCVD-Grown CdTe

Abstract

AbstractP-type CdTe can be produced via acceptor doping with As. However, as with other II/VI materials, the dopant behaviour is not simple, as there is the potential for compensating species to be formed from intrinsic defects and dopant-defect complexes. A further complication is introduced by the presence of grain boundaries in polycrystalline material. This study demonstrates that dopant concentration is a function of VI/II ratio in the growth ambient, and that resistivity is minimised for a dopant concentration of < 2 × 1018 at.cm-3. Grain size is also affected by the VI/II ratio, increasing slightly as the growth ambient becomes more Te-rich.