Photoluminescence and temperature-dependent Hall measurements of unintentionally doped HgCdTe epilayers were compared. These films were grown by liquid phase epitaxy and post-annealed under different conditions as follows: a p-type annealing was used to control the mercury vacancy concentration and a n-type annealing under saturated Hg atmosphere was used to fill the mercury vacancies. The comparison of the photoluminescence measurements with Hall effect measurements permitted the identification of the two acceptor energy levels of the mercury vacancy and the revelation of its negative-U property; corresponding to a stabilization of the ionized state V− of the mercury vacancy as compared to its neutral state V0.

Identification of the Double Acceptor Levels of the Mercury Vacancies in HgCdTe. F.Gemain, I.C.Robin, M.De Vita, S.Brochen, A.Lusson: Applied Physics Letters, 2011, 98[13], 131901