Photoluminescence of CdZnTe thick films obtained by close-spaced vacuum sublimation

Abstract

a b s t r a c tPolycrystalline Cd 1 À x Zn x Te thick films with thicknesses of about 30 μm have been deposited on a Mo coated glass substrate by means of close-spaced vacuum sublimation technique. X-ray diffraction measurements have shown that the films obtained have only cubic zinc blende phase. The influence of Zn concentration on the photoluminescence (PL) spectra of Cd 1 À x Zn x Te films was investigated. This let us determine the nature and energy structure of the intrinsic defects and residual impurities in the films. The presence of the most intense acceptor bound exciton A°X-line for x ¼ 0.10 and the lines of localized excitons (x ¼ 0.32 À 0.44) in PL spectra of Cd 1 À x Zn x Te films indicates their fairly good optical quality as well as the p-type conductivity. There were also other intensive broad PL bands, caused by the recombination of donor-acceptor pairs involving complex acceptor centers, extended defects of dislocation type, and microstress in the films. It was also established a correlation between the broadening of exciton lines and the values of microstress in Cd 1 À x Zn x Te thick films. Taking into account the energy position of exciton lines, the concentration dependence of the band gap for the Cd 1 À x Zn x Te thick films is presented.

Effect of thickness on physical properties of electron beam vacuum evaporated CdZnTe thin films for tandem solar cells

“…A study on the impact of thickness on physical properties is of great significance for fabrication of tandem solar cells. An enormous amount of research work on structure, optical and optoelectronic properties of CdZnTe thin films have been reported by the researchers across the world [17][18][19][20][21][22]. However, there is lack of reports on the effect of film thickness on structural, optical, electrical and surface morphological properties of CdZnTe films.…”

Effect of Different Selenium Precursors on Structural Characteristics and Chemical Composition of Cu2ZnSnSe4 Nanocrystals

“…At the same time, the value of the lattice parameter с with an increase in the NCs synthesis time increases, practically reaching at τ = 60 min (с UС = 1.13298 nm) values typical for stoichiometric materials (c UС = 1.13330 nm) [68][69][70]. A similar increase is observed for the ratio of these quantities c UС /2a UС , which at synthesis times τ = (45-60) min begins to exceed the reference data values.…”

“…The average size of CSR and the level of microdeformations (ε) in the obtained samples were calculated by the physical broadening of the diffraction peaks (112), ( 204), (312) using the following equations [65][66][67][68]:…”

“…The methodology for studying the structural, microstructural, chemical properties of the nanoparticulate products is described in detail in our previous works [57,59,[66][67][68].…”

Raman Characterisation of Cd1-xZnx Te Thick Polycrystalline Films Obtained by the Close-Spaced Sublimation

“…[27,28], using FWHM of (111) diffraction peak (Table I). Analogously to [25,29], the dependence of FWHM peak (111) and therefore the dependence of CSD size and microstrains level on x had a nonlinear behavior; in particular CZT4 and CZT5 samples, with x = 0.46 and x = 0.63 respectively, showed the maximal value of FWHM of (111) peak. This effect is explained by the following process.…”