Abstract :
Fourier transform infrared (FTIR) transmission, Hall effect, and nuclear resonance reaction measurements have been
carried out to investigate the effect of hydrogenation on the deep levels and the hydrogen depth profiling in nominally
undoped HgxCd I _xTe layers grown on undoped p-CdTe (211) B-orientation substrates by molecular beam epitaxy. After
hydrogenation, the FTIR spectra showed that the transmittance intensity increased in comparison to that of the as-grown
Hg xCdl_ xTe and that the absorption edge shifted to the short wavelength range. Hall effect measurements showed that the
cartier concentration decreased and the mobility increased after hydrogenation. After hydrogenation, p-type HgxCd I _xTe is
converted to n-type HgxCd 1 _xTe with high resistivity. Nuclear resonance reaction measurements show that the concentration
and the penetration depth of the hydrogen atom in n-Hgo.77Cdo.23Te are 3.5% and 640 A, respectively. The areal density
of the hydrogen-containing layer at the surface of the hydrogenated n-Hgo.77Cdo.23Te film is 4.39 × 1015 atoms/cm 2. These
results indicate that hydrogen atoms not only effectively passivate impurities or defects in the Hg xCdl_ xZe film but also
change the carder type of p-HgxCd I _xTe. © 1997 Elsevier Science B.V.
