IONIZATION-ENERGY OF ACCEPTORS IN AS-DOPED HGCDTE GROWN BY MOLECULAR-BEAM EPITAXY

The p-type activation of arsenic (As) in (211)B mercury cadmium tellur ide (HgCdTe) grown by molecular beam epitaxy (MBE), with different com positions covering the 3-5 and 8-14 mu m atmospheric transmission wind ows and after annealing at 300 degrees C is reported. The composition and thickness of the MBE layers were determined from Fourier transform infrared transmission measurements at room temperature. The ionizatio n energies of shallow accepters related to As in MBE HgCdTe layers wit h different Cd compositions have been obtained by fitting variable tem perature Hall measurement results to a two-band nonparabolic Kane mode l. The results indicate that As incorporated during the MBE growth can be activated to provide a shallow acceptor level in MBE HgCdTe and th e ionization energy of the As acceptor decreases with decreasing Cd co mposition, in agreement with the theory. (C) 1998 American Institute o f Physics.