TY  - JOUR
A1  - Kraus, M. M.
A1  - Becker, Charles R.
A1  - Scholl, S.
A1  - Wu, Y. S.
A1  - Yuan, S.
A1  - Landwehr, G.
T1  - Infrared photoluminescence on molecular beam epitaxially  grown Hg\(_{1-x}\)Cd\(_x\)Te layers
N2  - No abstract available
Y1  - 1993
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-38053
ER  - 
TY  - JOUR
A1  - Becker, Charles R.
A1  - Wu, Y. S.
A1  - Waag, A.
A1  - Kraus, M. M.
A1  - Landwehr, G.
T1  - The orientation independence of the CdTe-HgTe valence band offset as determined by x-ray photoelectron spectroscopy
N2  - No abstract available
Y1  - 1991
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-30784
ER  - 
TY  - JOUR
A1  - Herrmann, K. H.
A1  - Happ, M.
A1  - Möllmann, K.-P.
A1  - Tomm, J. W.
A1  - Becker, Charles R.
A1  - Kraus, M. M.
A1  - Yuan, S.
A1  - Landwehr, G.
T1  - A new model for the absorption coefficient of narrow gap (Hg,Cd)Te that simultaneously considers band tails and band filling
N2  - A semiempirical model is presented that correlates the broadening of the absorption edge with both transitions below the energy gap and with transitions by the Kane band model. This model correctly fits both the absorption and luminescence spectra of narrow-gap (Hg,Cd)Te samples that have been grown by the traveling heater method as well as by molecular-beam epitaxy. The accuracy of the band-gap determination is enhanced by this model.
Y1  - 1993
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-37894
ER  - 
TY  - JOUR
A1  - Becker, Charles R.
A1  - He, L.
A1  - Regnet, M. M.
A1  - Kraus, M.M.
A1  - Wu, Y. S.
A1  - Landwehr, G.
A1  - Zhang, X. F.
A1  - Zhang, H.
T1  - The growth and structure of short period (001) Hg\(_{1-x}\)Cd\(_x\)Te-HgTe superlattices
N2  - Molecular beam epitaxially grown short period (001) Hg\(_{1_x}\)Cd\(_x\)Te-HgTe superlattices have been systematically investigated. Several narrow well widths were chosen, e.g., 30, 35 and 40 Å, and the barrier widths were varied between 24 and 90 Å for a particular well width. Both the well width and the total period were determined directly by means of x-ray diffraction. The well width was determined by exploiting the high reflectivity from HgTe and the low reflectivity from CdTe for the (002) Bragg reflection. Knowing the well and barrier widths we have been able to set an upper limit on the average Cd concentration of the barriers, \(\overline x_b\), by annealing several superlattices and then measuring the composition of the resulting alloy. \(\overline x_b\) was shown to decrease exponentially with decreasing barrier width. The structure of a very short period superlattice, i.e., 31.4 Å, was also investigated by transmission electron microscopy, corroborating the x-ray diffraction results.
Y1  - 1993
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-37858
ER  - 
TY  - JOUR
A1  - Wu, Y.S.
A1  - Becker, Charles R.
A1  - Waag, A.
A1  - Kraus, M. M.
A1  - Bicknell-Tassius, R. N.
A1  - Landwehr, G.
T1  - Correlation of the Cd-to-Te ratio on CdTe surfaces with the surface structure
N2  - We report here that reconstruction on (100), (1lIlA, and (1l1lB CdTe surfaces is either C(2X2), (2X2), and (l X I) or (2X I), (l X I), and (l X I) when they are Cd or Te stabilized, respectively. There is a mixed region between Cd and Te stabilization in which the reflected high-energy electron-diffraction (RHEED) patterns contain characteristics of both Cd- and Te-stabilized surfaces. We have also found that the Cd-to-Te ratio of the x-ray photoelectron intensities of their 3d\(_{3/ 2}\) core levels is about 20% larger for a Cd-stabilized (1lIlA, (1lIlB, or (100) CdTe surface than for a Te-stabilized one. According to a simple model calculation, which was normalized by means of the photoelectron intensity ratio of a Cd-stabilized (lll)A and aTe-stabilized (1l1lB CdTe surface, the experimental data for CdTe surfaces can be explained by a linear dependence of the photoelectron-intensity ratio on the fraction of Cd in the uppermost monatomic layer. This surface composition can be correlated with the surface structure, i.e., the corresponding RHEED patterns. This correlation can in turn be employed to determine Te and Cd evaporation rates. The Te reevaporation rate is increasingly slower for the Te-stabilized (Ill) A, (l1l)B, and (100) surfaces, while the opposite is true for Cd from Cd-stabilized (Ill) A and (Ill)B surfaces. In addition, Te is much more easily evaporated from all the investigated surfaces than is Cd, if the substrate is kept at normal molecular-beam-epitaxy growth temperatures ranging from 2oo·C to 300 ·C.
KW  - Festkörperphysik
Y1  - 1991
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-37789
SN  - 0163-1829
ER  -