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Thin films of Bi, Sb, solid solutions Bi 1-x Sb x , as well as multilayer structures Bi-Sb-Bi-Sb-from elementary sources were produced by pulsed laser deposition for optoelectronic applications. KBr crystals were used as substrates. The solid solutions Bi 1-x Sb x were obtained by co-evaporation of single targets of Bi and Sb. Structural investigations show that the performance of produced films depends on both the amount of material deposited per pulse of laser energy and the ratio of this amount for bismuth and antimony. Based on this the technological regimes of growth temperature and laser intensity ranges were determined in which single-crystalline growth of films with certain x is possible. Single-crystalline films of Bi 1x Sb x were obtained in the range of x (0.12-0.48), which corresponds to semiconductor state of this solution. The method of sequential deposition is used for fabrication of multilayer structures Bi/Sb with quantum-confined layers of bismuth. The growth regime with practically excluded interdiffusion of materials is found. Results of spectral investigations are shown to be in agreement with the theoretically predicted semimetal-to-semiconductor transition of bismuth as a result of quantum confinement.

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Results of investigations of thin-film heterojunctions nInSb–nGaAs, pInSb–nCdTe, thin films PbTe, Pb1−xSnxTe as well as periodic structures PbTe–Pba–PbTe produced by pulsed laser deposition (PLD) technique and possibilities of their application as IR photodetectors are discussed. PLD allows one to obtain abrupt interfaces of lattice-mismatched heterojunctions nInSb–nGaAs with large number of interface states. The sign reversal of photoresponse was observed in this structure in the wavelength range 3.5–6.5 µm. The wavelength at which the signal vanishes depends linearly on the applied bias voltage and shifts towards shorter wavelengths as the voltage increases. The device can operate as a sensitive null-signal detector and an infrared pyrometer. pInSb–nCdTe heterojunctions obtained by PLD in a regime of practically excluded interdiffusion of constituent materials reveal high sensitivity and fast operation (τ < 15 ns) in the spectral range 1.5–5.5 µm, which broadens with external voltage applied to the sample. This device can operate in photovoltaic, as well as in diode regimes. Optical memory effect was observed in heterojunction pInSb–nCdTe in the wavelength range 0.37–1.37 µm. PLD-produced PbTe, Pb1−xSnxTe films and periodic PbTe–Pba–PbTe structures with controllable parameters can be used as materials for detectors covering the wavelength range 1–10 µm.

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