http://dspace.nbuv.gov.ua:80/handle/123456789/114602 2026-04-05T14:26:52Z http://dspace.nbuv.gov.ua:80/handle/123456789/118146 Fabrication and characterization of ONO and tunnel oxide for 16k FLOTOX EEPROM cell Hashim, U.; Ayub, R.M.; On, K.S. The EEPROM process is one the hardest process to be developed. The performance of the EEPROM devices is normally judged on the programming speed, which relates to program high (erase) and program low (write) operations. It is essential that the program high and program low speed of the EEPROM cell is within 1ms with a programming voltage of not more than 16V. In this study, two experiments were setup to improve the programming speed. The first experiment was to increase the high voltage NMOS drain junction breakdown voltage with the source floating (HVNMOS BVDSF), and the second experiment was to scale down the ONO layer. The characterization work to increase the programming speed of the memory cell of 16k FLOTOX EEPROM has been carried out. P-field implant dose is optimized to have both the HVNMOS BVDSF and the p-field threshold voltage above 16V for fast programming. As a result, the threshold voltages of programming high and low operation are achieved at 4.35V and -0.77V respectively. Furthermore, by scaling down the nitride layer of ONO from 160A to 130A, the Vt program window is further improved to 4.5V and -0.94V for the program high and program low operations respectively. 2004-01-01T00:00:00Z http://dspace.nbuv.gov.ua:80/handle/123456789/118145 An improved contribution to optimize Si and GaAs solar cell performances Merabtine, N.; Amourache, S.; Bouaouina, M.; Zaabat, M.; Saidi, Y.; Kenzai, C. In resent years a considerable effort (experience, numerical simulation and theoretical prediction models) has been devoted to the study of photovoltaic devices characterised by high efficiency and low cost. The present study comes in way to contribute in the optimisation of the performance of Si an GaAs based (N/P) solar cells by the determination of physical and technological parameters giving the best photovoltaic conversion efficiency and a good spectral response. The four principal parameters that influence the operation of a solar cell are emitter and base doping, junction depth and base thickness. We have also taken into account the recent technique of elaboration of these structures. This study concerns the use of novel optimised values of electronic properties of GaAs and Si materials such as recombination velocity at surface (front and back). All enhancements recently reached: BSF, BSR layers, ARC anti reflection layer with textured surface, surfaces passivation, improved ohmic contacts are taken into account. I-V, P-V, EQE-λ characteristics obtained by PC1D similator on two different cells (Si and GaAs) under the global spectra AM1.5 have allowed us to get optimal cells. The comparison of the cells shows the advantage of given GaAs cells. The effect of solar concentration (1-100 suns) on cell operation has been studied. The later has contributed to the enhancement of the energetic efficiency. The effects different standard spetra such as AM1, AM1, 5G, and AM1.5D have been studied. The optimal values of physical parameters giving the best currents of short-circuit and voltages of open circuit as well as high conversion efficiency have been obtained for these two solar materials. 2004-01-01T00:00:00Z http://dspace.nbuv.gov.ua:80/handle/123456789/118144 Metrological support of satellite-borne UV-spectrometry using a backscattering technique Vashchenko, V.; Patlashenko, Zh.; Chernysh, E. Methods and physicotechnical facilities for examination, calibration and metrological testing of the main power spectral characteristics (total spectral sensitivity, scattered stray radiation, dynamic range) of the vehicle-borne ozone UV spectrometers in the spectral range 250-350 nm are considered. 2004-01-01T00:00:00Z http://dspace.nbuv.gov.ua:80/handle/123456789/118143 Properties of optical microsensor based on observation of whispering-gallery modes Datsyuk, V.V. Formulae for the intensity of the resonant spontaneous electric-dipole emission are derived in the framework of classical electrodynamics and quantum optics making allowance for inhomogeneous light absorption. Using these formulas, the physical backgrounds of a micrometer-sized optical sensor exploiting the properties of the whispering-gallery modes (WGMs) are studied. The role of the evanescent WGM's field in the considered optical effects is examined. 2004-01-01T00:00:00Z