International Journal of Nanoelectronics and Materials (IJNeaM)
Permanent URI for this collection
IJNeaM aims to publish original work of importance in the fields of nanoscience and engineering. Topics covered including Theoretical, Simulation, Synthesis, Design and Fabrication of Nanomaterials and Nanodevices; Metals, Insulators, and Semiconductors with a focus on Electronic, Structural, Magnetic, Optical, Thermal, Transport, Mechanical and other properties for the specialists in Engineering, Chemistry, Physics and Materials Science. IJNeaM accepts submission in the form of Reviews, Research Articles, Short Communications, and selected conference papers.
Copyrights and Limitations On Use
Browse
Browsing International Journal of Nanoelectronics and Materials (IJNeaM) by Issue Date
Results Per Page
Sort Options
-
PublicationSOI based nanowire single-electron transistors: design, simulation and process development( 2008-01)
;A. RasmiSamsudi SakraniOne of the great problems in current large-scale integrated circuits is increasing power dissipation in a small silicon chip. Single-electron transistors which operate by means of oneby-one electron transfer, is relatively small and consume very low power and suitable for achieving higher levels of integration. In this research, the four masks step are involved namely source and drain mask, Polysilicon gate mask, contact mask, and metal mask. The masks were designed using ELPHY Quantum GDS II Editor with a nanowire length and nanowire width of approximately 0.10µm and 0.010 µm respectively. In addition, the process flow development of SET and the process and device simulation of SET are also explained in this paper. The Synopsys TCAD simulation tools are utilized for process and device simulation. The results from the device simulation showed that the final SET was operating at room temperature (300K) with a capacitance estimated around 0.4297 aF. -
PublicationMetamagnetic behavior in Fe3Si and Fe3Al( 2008-01)
;N.E. Christensen ;J. KudrnovskýC.O. RodriguezThe electronic properties of Fe3Si and Fe3Al in the cubic DO3 structure are calculated within the local spin density approximation. There are two types of Fe atomic positions, one with tetrahedral symmetry ([A,C]) and one with cubic ([B]) point symmetry. The magnetic properties of the Fe[B] sublattice are similar to those of bcc iron (same symmetry), and this sublattice moment varies smoothly when the volume is varied. The [A,C] Fe atoms, on the other hand, exhibit magnetic phase transitions behavior when the volume is varied similar, and we refer to this as a metamagnetic behavior. The present calculations show that in Fe3Si and Fe3Al the transitions between various high-spin and low-spin phases are expected near and below the equilibrium volume, and experimental observation of the transitions should therefore be possible by means of high-pressure experiments. -
PublicationValence electron correlation energy embracing the diamond-lattice materials C through Sn( 2008-01)
;Norman H. MarchAngel RubioBy combining a recent result of March and Matthai for the energy gap G with a model of Rey and Savin, the correlation energy ec of the valence electrons embracing C, Si, Ge and Sn can be estimated. While Sn is thereby predicted to have ec near to the Ceperley-Alder jellium result corresponding to G = 0, diamond exhibits a dramatic reduction in correlation energy due to its large band-gap. -
PublicationMolecular dynamics simulation study of structural, elastic and thermodynamic properties of Tin below 286 K( 2008-01)
;A. Berroukche ;B. SoudiniK. AmaraMolecular-dynamics simulation has been used to investigate structural, elastic and thermodynamic properties of tin in the temperature range from 200K up to 286.36K. Calculations are carried out using the inter-atomic interactions model like a three-body potential of Tersoff. In the present work, a special interest has been made to the first form of tin (α-Sn), the reason why the temperature is below 286.36K. The calculated results of the lattice constant, the bulk modulus and its derivative, the total energy, and the pair distribution function are correctly described, in excellent agreement with other theoretical works as well as the experimental results. Our study enabled us to predict the thermodynamic properties like the specific heat and lattice thermal expansion. -
PublicationStudying the effect of X-ray radiation on the electrical properties of diodes 1N1405( 2008-01)Jassim M. NajimThe diode 1N1405 type silicon is subjected to different levels of energy and time irradiation. We have about three times; at every time we have measured the forward and reverse bias voltage of the diode to know what is the difference between the electrical properties of the same diode without irradiation of x-ray.
-
PublicationElectronic structure, magnetic and Fermi surface calculations of heavy-fermions superconductors compounds based on Nb3Sn( 2008-01)Badis BendjemilWe report a theoretical investigation of the electronic structures and Fermi surface of the heavy-fermion superconductors Nb3Sn. The electronic structures are investigated ab-initio on the basis of full-potential local orbital minimum-basis band- structure calculations (FPLO), adopting both the scalar- and fully relativistic formulations within the framework of the local spin-density approximation (LSDA). The possibility of a partial 4d localization occurring for compounds is discussed. The electronic structures of the Nb3Sn compounds are computed to be rather similar to the literature. Our total-energy calculations predict paramagnetic and ferromagnetic order to be favorable for Nb3Sn materials, which is, however, observed experimentally. Also, the calculated magnetic moment is 0.35 μB. Furthermore, the theoretical Fermi surfaces topology and the possible origins of the superconductivity are discussed. The Bardeen, Cooper and Schreiffer (BCS) energy gap and the Ginzburg-Landau (GL) parameter K for these compounds have been calculated from the Fermi velocity. We found strong indication suggesting the existence of a second superconducting (SC) gap in Nb3Sn. In addition, the average superconductivity-gap at zero temperature is calculated for this compound. The knowledge of energy gap value gives important information on the coupling scenarios. Our results provide an explanation between the electronic structures, the Fermi surface (FS) topology and two-band model of the superconductivity.
-
PublicationFP-LAPW calculations of ground state properties for AlN, GaN and InN compounds( 2008-01)
;B. Daoudi ;M. Sehil ;A. BoukraaH. AbidWe present first-principals all-electrons total-energy calculations concerning structural and electronic properties for the group III-V zinc-blend-like compounds AlN, GaN and InN using the full-potential linearized augmented plane wave (FP-LAPW) approach within the density functional theory (D.F.T) in the local density approximation (L.D.A) and the generalized gradient approximation (G.G.A) for the exchange correlations functional. Moreover, we have calculated bulk properties, including ground-state energies, lattice parameters, bulk modulus, its derivatives, cohesive energy and band structures. We find that the GGA yields improved physical properties for bulk AlN compared to the LDA. For GaN and InN, essentially no improvement is found: the LDA exhibits over binding, whereas the GGA shows a tendency for under binding. The degree of under binding and the overestimation of lattice parameters as obtained within the GGA increase on going from InN to GaN. Band structures are found to be very similar within the LDA and the GGA, for AlN, GaN and InN, therefore, the GGA does not offer any significant advantages. -
PublicationFirst-principles study of cubic BxGa1-xN alloys( 2008-01)
;A. Lachebi ;H. Abid ;M. DrizY. Al-DouriWe present first-principles calculations of the structural and electronic properties of cubic for different concentrations x of ternary alloy BxGa1-x N. The computational method is based on the full-potential linearized augmented plane wave method (FP-LAPW). The exchange and correlation energy is described in the local density approximation (LDA) and generalized gradient approximation (GGA). We have investigated the effect of composition on the ground state properties, lattice parameters, bulk modulus, pressure derivative and band gap of the zinc blend BN, GaN. The results obtained are in a good agreement with experimental and theoretical values concerning the variation of the gaps and crossover direct, indirect band gap and the bowing parameter. A reasonable agreement is found from the comparison of our results with other theoretical calculations. -
PublicationSwift heavy ion effects in Gallium Nitride( 2008-01)
;S. Mansouri ;P. Marie ;C. Dufour ;G. Nouet ;I. Monnet ;H. Lebius ;Z. BenamaraY. Al-DouriGaN layers were irradiated at room temperature with swift heavy ions. AFM (atomic force microscopy) images of specimens irradiated under grazing incidence show tracks. With 74 MeV Kr, the contrast is very faint unlike for 92 MeV Xe and 104 MeV Pb. This behavior indicates that the electronic energy loss threshold to produce tracks at grazing incidence is around 17keV/nm. These tracks consist of two parts, one with a rather homogeneous contrast, and a second with regularly spaced dots. Measurements in the bulk region after irradiation with 132 MeV Pb ions show tracks with a diameter of about 3 nm. -
PublicationStudy of intersubband transitions in Si1-xGex/Si quantum wells using 14-band k×p model( 2008-01)
;W. Liu ;D. H. Zhang ;T. H. Loh ;W.J. Fan ;S. F. YoonN. BalasubramanianOptical intersubband transitions (ISTs) for both in-plane polarization (TE) and normalto-plane polarization (TM) in p-type Si1-xGex/Si multiple quantum wells (MQWs) are investigated using 14-band k⋅p model combined with the envelope-function Fourier expansion method. The results show that the amplitudes of different intersubband transitions for TE and TM polarizations, and the overall absorption vary regularly with the well width as it affects the distribution of bound and continuum excited states directly, and TE mode absorption dominates in all the QWs studied. This work provides useful information for design and analysis of Si1-xGex/Si quantum well infrared photodetectors (QWIPs). -
PublicationModelling of the film thickness effecton the carrier's mobility in polysilicon thin film transistors( 2009-01)
;Y. Bourezig ;B. Bouabdallah ;S. MansouriF. GaffiotThe transfer characteristics modelisation of the Mosfet's structure allows us to simulate the doping effect, the grains size, the layer thickness as well as others parameters of the transistor. The purpose of this work is to study the effect of the layer thickness on the carrier's mobility in the channel. For that, a two-dimensional modelling of the electrical conduction in amorphous silicon Mosfet's is used. It is based on the solving of Poisson's equation and the two continuity current equations of electrons and holes, and takes into account of the properties of polysilicon material, such as a density of trapped states formed by two exponential band tails, and gaussian state distribution for the charge carriers. The numerical model assumes a drift- diffusion mechanism in the crystalline regions in series with a thermionic emission mechanism for carriers overcoming the grain boundary potential barrier. In order to validate the conduction model, we also incorporate the effect of the electrical field on the generation carriers at grain boundary traps. The transfer characteristics are studied in function of film thickness, then the carrier's mobility. The results show that, the surface field affects only the low thicknesses, the variation of this field as a fucntion of film thickness is sufficient to expalin the behaviour of channel mobility. For high thicknesses, the field effect mobility is controlled by intergranular barriers of potential. -
PublicationNanotechnology development status in Malaysia: industrialization strategy and practices( 2009-01)
;Elley NadiaShahrir SallehMalaysia has started it own micro-technology and nano-technology development since the early millennium year of 2000 and arise until this day. Some key plans have proven effective and others fairly not. Status about strategies and practices planned in Malaysia with some relevantfinding through experiences in industries collaboration observations and UniMAP involvement in nanotechnology are presented in this paper. Some suggestion and ideas are also presented. -
Publication2D-Modelling for the simulation of current-voltage characteristics in polysilicon schottky diode deposited by LPCVD and SAPCVD methods.( 2009-01)
;Nadia Benseddik ;Mohammed Amrani ;Zineb BenamaraTayeb Mohammed-BrahimThe aim of this work is to compare the quality of the Schottky contact obtained between Silver and the un-doped polysilicon layer deposited on glass substrate (Corning 1737) by using two techniques: Lower Pressure Chemical Vapor deposition LPCVD (LPCVD sample) and Sub Atmospheric Pressure Chemical Vapor Deposition SAPCVD (SAPCVD sample). A non ideal measured foward bias I-V characteristic has been observed. The elctrical parameters are evaluated such as ideality factor (4.94 and 6.46), barrier height (0.57 eV and 0.50 eV), saturation current (6.74x10ˉ³ mA and 2.14x10ˉ² mA) and series resistance (960Ω and 2300Ω), respectively on LPCVD and SAPCVD samples. Two-dimensional (2D) model of I-V characteristics taking into account the localization of traps states in the grain boundaries is developed. We are also considered the U-distribution of traps states in the band gap. A good adjustment is obtained between measurement and simulation of I-V characteristics and gives the energetic traps states distribution. The comparison of the performance of the two polysilicon layer deposition techniques has been analyzed and discussed. The experimental current curves are well fitted by this model which gives the energetic traps states distribution in the band gap. A good quality polycrystalline can be obtained using LPCVD technique but it is possible to deposit films with SAPCVD technique which it may be interesting candidate for the fabrication of solar cell. -
PublicationElectrical and structural properties of flash evaporation InSb thin films( 2009-01)
;S. K. J. Al-Ani ;Y. N. Obaid ;S. J. KasimM. A. MahdiIndium antimonide (InSb) thin films were prepared on glass substrates by flash evaporation technique of a stoichiometric bulk of InSb at different substrate temperatures Ts= (300,320,350)°C. Films thickness were in the range of t= (0.2 -0.6) µm. X-ray diffraction patterns on InSb powder and thin films were given. The patterns showed that all films were stoichiometric and the crytallinity degree was improved with increasing of the substrate temperature and film thickness. The Hall effect measurements at room temperature showed that all films have n-type conductivity except the film of 0.2 µm thickness prepared at Ts=350 °C was p-type conductivity. The electrical cnductivity was studied in temperature range (25-200) °C and it was decreased with increased the substrate temperature for all samples. The carrier's mobility at room temperature was found to be increased with film thickness and substrate temperature. -
PublicationMultilayer antireflection coatings model for red emission of silicon for optoelectronic applications( 2009-01)
;Kifah Q. SalihN. M. AhmedA model, based on the Transfer Matrix Method (TMM) of multilayer is used to evaluate the transmittance at the central wavelength 720 nm of Si when using Ge, SiO2 nd Si as multilayer thin film coatings. In this study, the results indicate that the transmissivity of ~ (720-750) nm emission of Silicon as emitter is affected significantly by multilayer thin film coatings of Ge, SiO2 and Si. Si/SiO2/Air and Si?Ge/Si/SiO2/Air show high transmissivity 92% and ~100% at central wavelength design (720nm) respectively. Uncoated Si surface shows low transmissivity ~66%. The width of the high-transmittance region of Si/Ge/Si/SiO2/Air is less than Si/SiO2/Air. The origin of the red emission of Si has been investigated. -
PublicationDescription of yrast states and deformation changes in Tantalum nuclei (Ta)( 2009-01)N. MansourThe gamma - ray studies of 167Ta nucleus will be studied and several rotational decay sequences are identified. In these nuclei values for the effective moment of the inertia are suggested which reproduces the energies of the non-yarst states, that are populated in decay of the isomer. The results are discussed in comparison of the energy level patterns for the tantalum isotopes with exiting data in the neighboring nuclei and thus has been done by studding the changes in deformation through the so called "Gaige Plots"
-
PublicationApplication of synopsys' taurus TCAD in developing CMOS fabrication process modules( 2009-01)
;Chin Seng FattS. SakraniTechnology CAD (TCAD) refers to the use of computer simulation to model semiconductor processing and devics operation. TCAD has two major functions namely process simulation and device simulation. It performs the semiconductor process simulation and the device simulation by taking the description of the transistor layout input to stimulate the fabrication process and device behavior before the actual silicon is made. this paper illustrates the use of Synopsys' Taurus TCAD to develop and stimulate the fabrication and electrical behavior of NMOS and PMOS transistors in the complete CMOS process flow. Illustration also include how mask information extracted from a layout by Taurus Layout is used by TSUPREM-4 to produce an output file containing complete structure, mesh and doping information that can be read into MEDICI device simulator to extract electrical characteristics. The specified process includes, not only steps required to stimulate a MOSFET device, but also all steps of the hypothetical CMOS process. -
PublicationEstimation of thermal contact resistance in metal-plastic interface of semiconducting electronic devices( 2009-01)
;S. A. Oke ;A. A. Oyekunle ;T. A. O. SalauA. A. AdegbemileFor decade, thermal contact resistance (TCR) has been measured experimentally. Unfortunately, the database, which should regularly support decision-making on TCR coefficients, seems not to exist. Thus, companies result to using outdated or irrelevant data that limits lifespan of electronics devices, their performance and reliability. This paper mathematically models the problem of TCR between two media (plastic-metal interface) in semi conductors with reference to resistance and the flow of heat accross or interface of two surfaces that area in contact, particularly in engineering applications. In this paper, a semiconductor/heat sink assembly is used to model the behaviour of thermal contact resistance. A cylindrical shaped semi-conductor was conceptualised, with the governing differential equations derived and the boundary conditions for the problem stated. The effect of parameters such as surface roughness, contact pressure, density of interstitial gas, heat capacity, thermal and mechanical properties on the temperature at the center of the semi-conductor was studied. From the analysis, it can be inferred that by effectively lowering thermal contact resistance, efficient heat tranfer results, which helps to prolong the life and reliability of the semi-conductor. The current work is motivated to fill an important gap that may be beneficial to practitioners in the semi-conductor industry. -
PublicationFirst-principles calculations of the structural and electronic properties of AlN, GaN, InN, AlGaN and InGaN( 2009-01)
;Abbès Beloufa ;Zouaoui Bensaad ;Bel-Abbes Soudini ;Nadir Sekkal ;Abdelallah BensaadHamza AbidFirst principles calculations are carried out for A1N, GaN, InN, A1Gan and InGaN in various crystal structures. The computational method used to investigate the structural and the electronic properties is the full potential linear muffin-tin orbital (FP-LMTO) augmented by a plane-wave basis (PLW). Exchange-correlation has been accounted for within LDA using hte exchange-correlation potential calculated by Vosko et al. and Perdew et al. The latter parameterisation takes into consideration the generalized gradient approximation (GGA). The results of the calculated properties for the considered compounds in the zincblende and wurtzite phases are discussed and compared to the theoretical works as well as to the experimental data. We have also applied this computational method to A1GaN and InGaN alloys to check its transferability to predict the structural and electronic properties from those of their parent compounds. -
PublicationElectronic and positronic studies of zinc-blend boron phosphide BP underpressure( 2009-01)
;M. Sehil ;H. Abid ;A. LachebiY. Al-DouriWe analyze the effect of the pressure variations on the electron and the positron distributions in the boron phosphide. On the basis of the pseudopotential band structure calculations (EPM) and the independent particle approximation (IPM), the electron and the positron wave functions are derived, respectively. The resulting wave functions are used to compute the corresponding charge densities along the <111> axis. The integrated electron-positron momentum densities, for different pressures, are calculated along the (001) and (110) directions. The results are used to analyze the evolution of the bonding properties and to predict how pressure could affect positron annihilation results in the boron phosphide.