Nanoscale effects of arsenic incorporation in CdTe grown by molecular beam epitaxy

摘要

Difficulties with p-type doping in CdTe based photovoltaics prompted the growth of epitaxial As-doped CdTe to fundamentally understand dopant incorporation limits and activation. At high levels of As, HgCdTe and CdTe have shown drastic decreases in electrical activity, but the mechanism has been unknown. Atom probe tomography analysis of As-doped CdTe revealed clustering of As. Particularly, the authors found that As tends to substitute more for Cd rather than the expected Te. According to this information, a detailed evaluation of post-growth annealing temperatures to reduce clustering and increase electrical activity is warranted.