Search results

Sort By:

Limit search:

Raman Characterisation of Cd_{1-x}Zn_x Te Thick Polycrystalline Films Obtained by the Close-Spaced Sublimation

100%

Znamenshchykov Y., Kosyak V., Opanasyuk A., Dorda V., Fochuk P., Medvids A.

Acta Physica Polonica A

2017

vol. 132

issue 4

1430-1435

In this work, we studied the Raman spectra of thick polycrystalline Cd_{1-x}Zn_x Te (CZT) films with x ranged from 0.06 to 0.68. Additionally, the surface morphology and structural properties were studied in order to determine the crystalline quality of the samples. The Raman spectra had a two-mode behavior typical for CZT solid solution and showed CdTe- and ZnTe-like longitudinal and transverse optical modes. The relationship between the frequencies of CdTe- and ZnTe-related modes on x was studied. We observed the deviation of the compositional dependence of phonon mode frequencies for polycrystalline CZT films in comparison with a similar dependence for CZT single crystals. Such deviation was caused by the effect of structural defects in polycrystalline films on frequencies of vibrational modes. The values of excitation wavelength, which allow achieving of high signal-to-noise ratio on the Raman spectra of CZT films with different zinc concentration in the result of resonant enhancement of phonon modes intensities, were experimentally determined.

Comparative study of ZnO layers prepared by PLD from different targets at various oxygen pressure levels

52%

HaÅ¡ko D., Bruncko J., Vincze A., Uherek F. e.

Open Physics

2009

vol. 7

issue 2

345-349

Two series of polycrystalline zinc oxide (ZnO) layers, from Zn or ZnO targets, were grown on silicon (1 1 1) substrates by pulsed laser deposition (PLD) at ambient oxygen pressure levels, stepwise increased from 1 to 35 Pa. For ablation of targets, a pulsed Nd:YAG laser was used. The structural and morphological properties of the layers were investigated by scanning electron microscopy (SEM), atomic force microscopy (AFM), and secondary ion mass spectrometry (SIMS). The SEM images of ZnO layers in SE mode show a uniform granular structure and modified surface morphology, depending on oxygen pressure. The mean grain size in height and lateral directions decreases with an increase of oxygen pressure from 1 to 5 Pa, while a subsequent rise of oxygen pressure from 5 to 35 Pa will cause an increase in the grain size. The AFM measurement revealed that the surface structures of zinc oxide layers grown from different targets were similar, and the layers formed at an ambient oxygen pressure of 5 Pa exhibited the smallest values of calculated roughness and granularity. SIMS depth profiling analyses confirmed that the ZnO composition was homogenous across the layer, up to the abrupt change of chemical composition at the interface between the ZnO layer and the Si substrate.

Refine search results

1 Acta Physica Polonica A

1 Open Physics

1 2017

1 2009

1 Bruncko J.

1 Dorda V.

1 Fochuk P.

1 HaÅ¡ko D.

1 Kosyak V.

1 Medvids A.

1 Opanasyuk A.

1 Uherek F. e.

1 Vincze A.

1 Znamenshchykov Y.

Search results

Raman Characterisation of Cd_{1-x}Zn_x Te Thick Polycrystalline Films Obtained by the Close-Spaced Sublimation

Comparative study of ZnO layers prepared by PLD from different targets at various oxygen pressure levels