Optical absorption of un-implanted and implanted HgCdTe

Optical absorption coefficients of un-implanted and implanted HgCdTe have been measured in a range of temperatures and compositions. The index of refraction for photon energies larger than bandgap was obtained. With the measured index of refraction, large values of the optical absorption coefficient were extracted from measured transmission spectra. The obtained optical absorption coefficient agrees very well with the Kane's model. The measured optical absorption coefficient at the bandgap linearly depends on temperature. Cutoff photon energy for highly n-type doped HgCdTe resulted from ion implantation of boron at 150 keV energy and with 1 x 10(15) cm-(2) dose is larger than that for the un-implanted HgCdTe. The magnitude of the shift is consistent with the prediction of the theory of Moss-Burstein shift, using measured doping profile.