Raman Scattering Study of H₂O₂-Etched Zn_0.1Cd_0.9Te Surfaces

Abstract

Raman study of as-grown and H 2 0 2 -etched surfaces of Zn 0 .,Cd 0 .Te single crystal has been performed. A distribution of Te precipitates on the surface of as-grown ZCT, which increases after etching, has been encountered. With high irradiation powers, due to the oxidation of the surfaces, new bands of TeO 3 2 -are evolved. A downward shift in the peak position, as well as a halfwidth broadening, of all Raman modes has been observed with increasing laser power. The phenomenon, due to the formation of insulating oxide of tellurium in a dispersion of Te precipitates and vice-versa, has been attributed to the quantum confinement of phonons.

Low-Temperature Fourier Transform Raman Scattering Characterization of Cd1?xZnxTe Surfaces by Different Treatments

“…1, which could be assigned to the presence of Te on Cd 0.96 Zn 0.04 Te surfaces. Te phonons that have been detected on various Cd 1--x Zn x Te surfaces [3][4][5][6][7] are observed here. By comparing the results obtained by different authors, Te phonon peaks are somewhat different in frequency.…”

“…Raman scattering (RS) is extensively used to characterize the Cd 1--x Zn x Te surface, especially the Te elemental deposits on the surface that in a sense directly reflect structural defect behavior near the surface [3][4][5][6]. The difficulty and complexity of Raman measurements of the Cd 1--x Zn x Te surface exposed to higher irradiation power, have been considered [6] and primarily were correlated with surface state variation induced by laser irradiation.…”

“…The difficulty and complexity of Raman measurements of the Cd 1--x Zn x Te surface exposed to higher irradiation power, have been considered [6] and primarily were correlated with surface state variation induced by laser irradiation. For example, Te precipitates on Cd 1--x Zn x Te surface increase in density after high-power-laser irradiation and the occurrence of surface oxidation [7].…”