Due to the unique physical properties of CdTe and ZnTe compound, thin films of this materials have wide application to produce a range of devices for microelectronics. It has resulted in necessity of improvement existing and search of new methods of production qualitative two-component semiconductors layers with the predetermined structural and electrophysical characteristics.
For condensation chalcogenide thin films we use a "hot wall" epitaxy method, which due to the design features of the evaporator allows to provide the good control of technological parameters of vacuum evaporation and as result to obtain layers with predetermined structure. The CdTe and ZnTe layers was obtained on glass and metallized substrate with the coordinated linear expansion factor of metal and semi-conductor films in wide range of the evaporator and substrate temperatures.
The research and analysis of the films chemical composition was carried out by X-ray spectrography, optical and scanning electron microscopy. The structural analysis of the films included diffraction research of phase composition, determination type and period of crystal lattice, growth texture and crystallites size in polycrystalline layers. To study films point defects structure, the spectral and conductivity temperature dependences, voltage-current characteristic of samples were analysed. The measurements were taken both in sandwich and in planar structures of thin films. The theoretical justification of the received results was performed with the help of the quasichemical point defects theory, and at study deep traps centers one used theory of space charge limited currents. Modelling of ensemble of point defects in films depending on physicotechnological conditions of condensation was realized for two extreme cases: full equilibrium and quenching. By results of modeling were determined predominant point defects in samples.
This researches allow to determine growth conditions of high-performance CdTe and ZnTe thin films.
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