Growth, structure, and properties of GaAs-based (GaAs)1–x–y(Ge2)x(ZnSe)y epitaxial films

Resumo

The possibility of growing the (GaAs)_1–x–y(Ge₂)_x(ZnSe)_y alloy on GaAs substrates by the method of liquid-phase epitaxy from a tin solution–melt is shown. X-ray diffraction shows that the grown film is single-crystal with the (100) orientation and has the sphalerite structure. The crystal-lattice parameter of the film is a_f = 0.56697 nm. The features of the spectral dependence of the photosensitivity are caused by the formation of various complexes of charged components. It is established that the I–V characteristic of such structures is described by the exponential dependence I = I₀exp(qV/ckT) at low voltages (no higher than 0.4 V) and by the power dependence J ~ V^α, where the exponent α varies with increasing voltage at high voltages (V > 0.5 V). The results are treated within the framework of the theory of the drift mechanism of current transfer taking into account the possibility of the exchange of free carriers within the recombination complex.