Semicond. Physics Quantum Electronics & Optoelectronics, 2012, № 2

Residual stresses and piezoelectric properties of the HgCdTe – based compound heterostructures under the anisotropic deformation restriction

Sun, 01 Jan 2012 00:00:00 GMT

Residual stresses and piezoelectric properties of the HgCdTe – based compound heterostructures under the anisotropic deformation restriction Smirnov, A. B. Narrow-gap mercury cadmium telluride thin films grown by MBE methods onto various substrates (HgCdTe/Si, HgCdTe/GaAs) were investigated as a piezoelectric heterostructure for IR detection. Mechanical stresses at the layer-substrate interface were analyzed. It was determined that for [310] oriented MCT-based structures under the anisotropic restriction of the deformation the nonzero shear components of the strain tensor arise and stress induced piezoelectric polarization is generated. Existence of the built-in electric field in the strained MCT-based heterostructure results in the spatial separation of the nonequilibrium carriers and the possibility of the room temperature detection of the IR radiation is realized.

Effect of pressure on the properties of Al-SiO₂-n-Si structures

Sun, 01 Jan 2012 00:00:00 GMT

Effect of pressure on the properties of Al-SiO₂-n-Si structures Vlasov, S.I.; Ovsyannikov, A.V.; Ismailov, B.K.; Kuchkarov, B.H. We investigated the effect of hydrostatic pressure on relaxation characteristics of the three-layer Al-SiO₂-n-Si structures. It was found that 20 min exposure to a pressure of 8 kbars results in reduction of the integral density of surface states, while exerting no influence on the generation centers in the bulk.

Intensities of quantum transitions in hexagonal nanotubes within the exciton spectral range

Sun, 01 Jan 2012 00:00:00 GMT

Intensities of quantum transitions in hexagonal nanotubes within the exciton spectral range Makhanets, O.M.; Tsiupak, N.R.; Voitsekhivska, O.M. The theory of exciton spectrum and intensities of interband quantum transitions in multi-shell hexagonal semiconductor nanotube is developed within the effective masses and rectangular potentials approximations using Bethe variational method. The obtained theoretical results well explain the experimental position of luminescence peak for GaAs/AlxGa₁-xAs nanotubes.

Application of ferroelectrics to create electroluminescent indicators of temperature

Sun, 01 Jan 2012 00:00:00 GMT

Application of ferroelectrics to create electroluminescent indicators of temperature Boyko, V.G.; Zayats, N.S. In this article, temperature dependences of brightness of thin film electroluminescent emitters (TFELE) based on metal-dielectric-semiconductor-metal (MDSM) structures with ceramic ferroelectric dielectric have been considered. Their comparable analysis with the temperature dependence of dielectric themself has been made. Literature data concerning this question have been briefly discussed. The conclusion about the possibility to use ferroelectrics (ceramics based on BaTiO₃, AlN, LiNbO₃) with a pronounced thermal dependence of capacitance characteristics to produce the temperature light indicators has been made. The design of a new temperature sensor can be realized in several ways. For example, in the form of the scales with a moving luminous column or separate lighting dots, depending on how clearly Curie peaks are observed on the temperature curves of dielectric permittivity.