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 telluride ( HgCdTe) grown by molecular beam epitaxy (MBE), with different compositions covering the 3-5 and 8-14 mm atmospheric transmission windows and after ann ealing at 300 degrees C is reported. The composition and thickness of the M BE layers were determined from Fourier transform infrared transmission meas urements at room temperature. The ionization energies of shallow acceptors related to As in MBE HgCdTe layers with different Cd compositions have been obtained by fitting variable temperature Hall measurement results to a two -band nonparabolic Kane model. The results indicate that As incorporated du ring the MBE growth can be activated to provide a shallow acceptor level in MBE HgCdTe and the ionization energy of the As acceptor decreases with dec reasing Cd composition, in agreement with the theory. (C) 1998 American Ins titute of Physics. [S0003-6951(98)01231-5].