bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhanced Degradation in P+-Poly PMOSFETs With Oxynitride Gate Dielectrics Under Hot-Hole Injection
Authors: Chen Y. Y. , Gardner M. , Fulford J. , Wristers D. , Joshi A. B. , Kwong D. L. 
Published: April 2011

ABSTRACTIn this paper, a significant degradation under hot hole injection is observed in P+ -poly PMOSFETs with oxynitride gate dielectrics. In our study, both oxynitrides formed by gate oxide grown on Nitrogen Implanted Si Substrates (NISS) and NO-annealed SiO2 oxynitride gate dielectrics are used and compared to control SiO2 gate dielectrics of identical thicknesses. A physical model responsible for such enhanced degradation in PMOSFETs with oxynitride gate dielectric is proposed. It is shown that the hole injection barrier lowering as a result of the nitrogen-rich layer at the SiO2/Si interface in oxynitride is responsible for such enhanced degradation.
Ultra Thin High Quality Ta2O5 Gate Dielectrics Prepared by In-situ Rapid Thermal Processing
Authors: Luan H. F. , Lee S. J. , Lee C. H. , Mao A. Y. , Vrtis R. , Roberts D. , Kwong D. L. 
Published: April 2011

ABSTRACTIn this paper, ultra thin CVD Ta2O5 stacked gate dielectrics (Teq∼14Å-22Å) was fabricated by in-situ RTP processing. The leakage current of Ta2O5 devices is 103× lower leakage current compared to SiO2 of identical thickness for devices with Teq between 18Å-22Å. While Teq<18Å, the leakage current follows same train and J∼10−3A/cm2 for Ta2O5 stacked gate dielectrics with Teq=14Å. Superior interface properties and reliability have been obtained.
The Influence of Fluorine on Various Mos Devices
Authors: Innertsberger G. , Jurk R. , Felsner J. , Kakoschke R. , Yuwono B. , Schlösser T. , Krautschneider W. , Gschwandtner A. 
Published: April 2011

ABSTRACTThe influence of Vapor Phase Precleans leads to a different controllable fluorine content within the subsequently grown dielectric. The influence of the clean is discussed for non-volatile memory devices, advanced MOS transistors and ultra thin gate dielectrics. On the one hand, the Qbd values for in situ cleaned samples are lower than for wet cleaned samples. Performing cycle stress on the EEPROM devices, the tunnel oxide (7.5nm) degrades the quicker with the increase in fluorine concentration within the oxide. On the other hand, MOS transistor characteristics show a significant improvement on the negative bias temperature instability (NBTI) in the PMOS threshold voltage. MOS transistors with ultra thin gate dielectrics (1.5nm) show the expected significant increase of the saturation current compared with 0.35µm technology (tox = 7.5nm). Excellent times until soft breakdown for ultra thin dielectrics are found when the in situ cleaning is used.
High Quality Ultra Thin CVD Si3N4Gate Dielectrics Fabricated By Rapid Thermal Process
Authors: Song S. C. , Luan H. F. , Gardner M. , Fulford J. , Allen M. , Kwong D. L. 
Published: April 2011

ABSTRACTIn this paper, we report performance and reliability of CMOS devices with ultra thin (<20Å) Si3N4gate dielectric fabricated by in-situ rapid thermal CVD (RTCVD) process, and compare with control SiO2devices of identical equivalent oxide thickness (Tox,eq). Ultra thin CVD Si3N4 devices show significantly lower gate leakage current, complete suppression of boron penetration, improved MOSFET performance, and enhanced reliability against electrical stress.
Interface Interstitial Recombination Rate and the Reverse Short Channel Effect
Authors: Rubin M.E. , Saha S. , Lutze J. , Nouri F. , Scott G. , Pramanik D. 
Published: April 2011

ABSTRACTExperiment shows that the reverse short channel effect (RSCE) in nMOS devices is critically impacted by the inclusion of nitrogen in the gate oxide. A higher concentration of nitrogen results in a lessened RSCE, i.e. more threshold voltage rolloff for smaller gate lengths. We propose that the additional nitrogen reduces the interstitial recombination rate at the interface, resulting in a smaller interstitial flux and therefore less transient enhanced diffusion (TED) of boron to that interface. To test this hypothesis, we simulate boron redistribution in one and two dimensional MOS capacitor structures, as well as full nMOS devices. We then present simulations calibrated to a 0.2 pim technology currently in production.
Mechanical Stress Characterization of Shallow Trench Isolation by Kelvin Probe Force Microscopy
Authors: Rueda Hernan , Slinkman James , Chidambarrao Dureseti , Moszkowicz Leon , Kaszuba Phil , Law Mark 
Published: April 2011

ABSTRACTmethod for characterizing the mechanical stress induced in silicon technology is described. Analysis by scanning Kelvin probe force microscopy (SKPM) coupled with finite-element (FE) mechanical strain simulations is performed. The SKPM technique detects variations in the semiconductor work function due to strain influences on the band gap. This technique is then used to analyze the strain induced by shallow trench isolation processes for electrical isolation. The SKPM measurements agree with the FE simulations qualitatively.
Estimation of the Number of Injected Interstitial Atoms during Nitrous Oxidation of Silicon
Authors: Skarlatos D. , Giles L.F. , Tsamis C. , Claverie A. , Tsoukalas D. 
Published: April 2011

ABSTRACTIn this work we use dislocation loops to monitor the interstitial injection during the oxynitridation (oxidation in 100% N2O ambient) of silicon at low temperatures (850–950 °C). The interstitials captured by the loops are measured using Transmission Electron Microscopy. The number of Si atoms released after oxynitridation was calculated from the difference in the total amount of atoms stored in the loops between oxidizing and inert ambient. We obtained that this number is larger compared with the respective under the same dry oxidation (in 100% O2 ambient) conditions.
Onset of Extended Defect Formation and Enhanced Diffusion for Ultra-Low Energy Boron Implants
Authors: Liu Jinning , Jones Kevin S. , Downey Daniel F. , Mehta Sandeep 
Published: April 2011

ABSTRACTTo meet the challenge of achieving ultra shallow p+/n source/drain extension junctions for 0.1 Oim node devices, ultra low energy boron implant and advanced annealing techniques have been explored. In this paper, we report the extended defect and boron diffusion behavior with various implant and annealing conditions. Boron implants were performed at energies from 0.25keV to lkeV and doses of 5 × 1014 cm−2 and 1 × 1015cm−2. Subsequent anneals were carried out in nitrogen ambient. The effect of energy, dose and oxide capping on extended defect formation and enhanced dopant diffusion was examined. It was observed that a thin screen oxide layer (35Å), grown prior to implantation, reduces the concentration of dopant in the Si by a significant amount as expected. This oxide also reduces the dislocation loops in the lattice and lowers diffusion enhancement of the dopant during annealing. The final junction depth can be optimized by using a low thermal budget spike anneal in a controlled oxygen ambient.
In-situ real time studies of nickel silicide formation
Authors: Tinani M. , Irene E.A. , Hu Y.Z. , Tay S.P. 
Published: April 2011

ABSTRACTNiSi, with its low resistivity and wide processing window (350 - 750°C), is an attractive candidate for use as a gate contact material. In order to follow the interface reaction that leads to the formation of NiSi in real time, ellipsometry and atomic force microscopy (AFM) were used to study changes on the surface resulting from the reaction between Ni and Si for various times and temperatures, and Rutherford Backscattering spectrometry (RBS) to determine compositional changes in the forming silicides. We report that ellipsometry can be used to monitor the various Ni-Si phases forming in real time, and we have observed agglomeration of the silicide, which has been reported to occur at 1000°C, at temperatures, as low as 550°C for long time anneals.
Remote True Temperature Pyrometry of Si Wafers: Theoretical and Practical Considerations
Authors: Glazman E. , Glazman A. , Thon A. 
Published: April 2011

ABSTRACTThe problems of real thermodynamic temperature measurement in semiconductor processing can be divided into fundamental and environmental. The first type arises from a-priori unknown and in process changing optical properties (emissivity) of the target wafer. Others have to do with the need to eliminate direct and indirect stray heat flux from entering into the sensor. We describe the advantages and pitfalls of various (passive and active) remote measurement methods. Experimental results of a novel emissivity independent technique for real time measurement in the range of 450–850°C with accuracy better than 1% for wafer emissivity in the range of 0.2 to 0.95 are given.
Ordering Kinetics and Diffusion in Some L12Alloys
Authors: Cahn Robert W. 
Published: April 2011

AbstractA comparison is made of, ordering kinetics for Cu3Au, (Tc= 388 ° C), Ni3Mn (Tc= 500° C) Ni3Fe (Tc= 517°C) and Ni3Al (Tc= 1450 ° C), which all form the L12superlattice, and these kinetics are correlated with diffusion data for the same alloys. Comparing different alloys, it is shown that for a fixed relaxation time for the establishment of order, the lower is the self-diffusivity, Ds, of the slowest-diffusing species, the higher the critical temperature, Tc, for the first appearance of order. Ni3A1, in particular, has an estimated Dsof about 5 orders of magnitude lower, on average, than the three other alloys. The implications of this inverse relation between Tcand Dsare discussed in relation to published models for diffusion in ordered alloys and ordering kinetics.
Neutron-Induced Vaporization of Superheated Liquids: Theory and Experiment
Authors: Apfel Robert E. 
Published: April 2011

AbstractMy interest in neutron-induced nucleation began with a simple and elegant demonstration in one of David Turnbull's classes in which a drop of water was superheated to about 250°C as it rose in a column of heated oil. As David Glaser, the inventor of the bubble chamber, so ably demonstrated, such superheated liquids are radiation sensitive. Our test system is a simple one. Halocarbon and hydrQcarbon drops are introduced into an aqueous holding gel under pressure at room temperature. As the pressure is released, the drops become superheated. Neutrons of sufficient energy will trigger vaporization of these moderately superheated drop detectors (SSDs), but gammas and x-rays will not unless the homogeneous nucleation limit is approached. We have performed measurements on the neutron energy threshold to produce nucleation in a number of different superheated materials at different temperatures. We have also developed a theory which indicates that of the energy deposited in a critical radius, only about 5% is effective in producing bubble formation. Both theory and experiment are discussed.
A Comparison of the Photophysical Properties of Thiolate-Capped CdS Quantum Dots with Thiolate-Capped CdS Molecular Clusters
Authors: Yeung Lee K. , Sooklal Kelly , Mahtab Rahina , Zhang Bin , Adams Richard D. , Murphy Catherine J. 
Published: April 2011

ABSTRACTIn the last several years, great advances have been made in the ability to synthesize semiconductor quantum dots with very narrow size distributions. Here, we report the synthesis of a series of thiolate-capped CdS quantum dots having reasonably narrow size distributions and make optical property comparisons to the crystallographically defined CdS molecular clusters having essentially “zero” size distribution. These clusters contain a “Cd10S4” core and thiolate/halide capping ligands. The luminescence of the molecular clusters, like the nanoparticles, is greatly influenced by the nature of the capping ligands. Additionally, the luminescence of the molecular clusters can be quite similar to that observed for their larger quantum dot counterparts.
Optical Properties of Cds Quantum Dots: The Key Role of the Spin-Orbit and Coulomb Interactions
Authors: Chamarro M. , Voliotis V. , Dib M. , Gacoin T. , Delerue C. , Allan G. , Lannoo M. 
Published: April 2011

ABSTRACTWe study theoretically and experimentally the effects of the Coulomb and the spin-orbit coupling on the electronic structure of small quantum dots. A tight-binding calculation with restricted configuration interaction is developed in a typical case: very small cubic quantum dots for which the electron-hole exchange interaction is of the order of magnitude of the spinorbit interaction. Experimentally, resonant photoluminescence and photoluminescence excitation are used to obtain information on a single size of CdS quantum dot obtained by a chemical growth method.
Absorption and Photoluminescence Study of Cds Quantum Dots: The Role of Host Matrix and Nanocrystal Size and Density
Authors: Rakovich Yu.P. , Rolo A.G. , Stepikhova M.V. , Vasilevskiy M.I. , Gomes M.J.M. , Artemyev M.V. , Jantsch W. , Heiss W. , Prechtl G. 
Published: April 2011

ABSTRACTIn this paper we present results of the absorption and photoluminescence (PL) of CdSdoped Si02 films fabricated by RF co-sputtering (semiconductor volume fraction f=1–15%, nano-crystallite's mean size 5–7nm) and matrix-free films of close-packed CdS nanocrystallites (f∼30%, size 2–5nm) produced by an original chemical method. The absorption spectra have been modelled using the modified Maxwell-Garnett model. This gives the e-h pair state energies and evidence of a strong absorption in the glass matrix containing CdS. The temperature dependence of the spectral position and broadening of the PL peak is analysed. It is concluded that a photo-generated hole is captured on an acceptor-type trap before the radiative recombination with a confined electron. The excitation of this ‘band-edge’ PL occurs through some states in the matrix and directly in the CdS crystallites for the two kinds of samples, respectively. The temperature coefficients of the optical transition energies for the nearly matrix-free films are similar to those of bulk CdS, while for the CdS/glass films they are smaller. This may be because of the different boundary conditions for the thermal expansion of CdS crystallites.
Stress and Deformation of Pzt Thin Film on Silicon Wafer Due to Thermal Expansion
Authors: Zang Ming , Polla Dennis L. , Zurn Shayne M. , Cui Tianhong 
Published: April 2011

AbstractStress and deformation of PZT thin films deposited on silicon wafers due to thermal expansion during the annealing process are modeled using a 3-D shell element of ANSYS. Two different designs of PZT thin films on the wafer are modeled. The first design is a PZT/Pt/Ti/silicon dioxide/silicon wafer, which is used for making acoustic emission sensors. The second design is a PZT/Pt/Ti/silicon dioxide/silicon nitride/silicon dioxide/silicon wafer, commonly used in fabrication of cantilever beams. For the design without the silicon nitride layer, the thermal stress of the PZT film is 298MPa, Pt 1280MPa, Ti 647MPa, the silicon dioxide layer is 228MPa, and the silicon wafer is 0.41–1.67MPa. For the design with silicon nitride, the thermal stresses are: PZT 301MPa, Pt 1280MPa, Ti 651MPa, silicon dioxide 226MPa, silicon nitride 416MPa, silicon dioxide 226MPa, and silicon wafer 1.05–4.23MPa. The residual stress of the PZT film is measured at 200–25OMPa for the design without silicon nitride, and 336MPa for the design with silicon nitride. Comparisons of the thermal stress with the tensile or proof stress of material for each layer indicate that thermal stress of the PZT film is slightly greater than its bulk tensile stress, that of Pt film is five times greater than its bulk tensile stress, and that of Ti film is approximately equal to its bulk tensile stress. The thermal stresses of silicon dioxide, silicon nitride, and silicon wafer layers are far smaller than their proof stresses.
Growth of (Ni,Zn)Fe2O4 Thin Films by Liquid Delivery Metal-Organic Chemical Vapor Deposition
Authors: Gangaware D. , Woolcott R. , Kingon A. I. , Roeder J. F. , Baum T. H. 
Published: April 2011

AbstractNi,Zn-ferrite (NZF) thin films are of interest for high frequency applications because of their high saturation magnetization compared to garnet films and their low eddy current losses compared to metal alloy films. Therefore there is an increasing need for methods to deposit single crystal ferrite thin films for incorporation into next generation microwave devices.Epitaxial thin films of NZF have been deposited by liquid delivery metal-organic chemical vapor deposition onto (100) oriented MgO substrates. The morphology, orientation and magnetic properties of the as-deposited films were investigated as a function of deposition temperature and pressure. X-ray diffraction (XRD) reveals highly oriented films with a film strain of 1.01% compared to bulk lattice parameters. Films with well saturated magnetic hysteresis were obtained under a number of conditions with values of saturation magnetization up to 270 emu/cc (3400 gauss) with relatively low coercive fields ~100 Oe. The influence of metal cation ratio on magnetic properties is discussed.
Compositional Design of Faraday Rotator Materials
Authors: Fratello V. J. , Licht S. J. , Brandle C. D. 
Published: April 2011

AbstractBismuth-doped rare-earth iron garnet thick films have become the material of choice for a wide variety of magnetooptic applications including optical isolators and circulators. Garnet compositional design and liquid phase epitaxial growth have been adapted to the requirements of these devices. Properties such as optical absorption, specific Faraday rotation, temperature dependence of Faraday rotation, saturation magnetization and temperature dependence of saturation magnetization can be controlled to a high degree. Introduction of nucleation induced coercivity has even allowed the elimination of a permanent bias magnet. However, in optimizing device performance and film growth, there are often tradeoffs among these properties. Material design is therefore a compromise based on the requirements of device designers.
Uniformity of Misfit Strain in Heteroepitaxial (Ba, Sr)Tio3 Films on SrRuO3/SrTiO3
Authors: Abe K. , Yanase N. , Sano K. , Fukushima N. , Kawakubo T. 
Published: April 2011

AbstractUniformity of lattice misfit strain was quantitatively evaluated in heteroepitaxial (Ba, Sr)TiO3 films which were deposited by radio-frequency magnetron sputtering on SrRuO3/SrTiO3 substrates. Due to lattice misfit strain, the (Ba, Sr)TiO3 films had a 3% longer c-axis than the inherent bulk of (Ba0.75Sr0.25)TiO3. As analyzed by Hall's theory, the uniformity of the strain was 0.3% of the c-axis (0.413 nm) and 9% of the elongation of the c-axis (0.015 nm). It was suggested by the comparative study of two specimens that there is a strong correlation between the quality of the ferroelectric hysteresis loop and the uniformity of the misfit strain in heteroepitaxial (Ba,Sr)TiO3 films.
Strain Inhomogeneity in Epitaxial Colossal Magnetoresistive La1-xCaxMnO3 Thin Films
Authors: Rao R. A. , Nath T. K. , Lavric D. , Eom C. B. , Tsui F. 
Published: April 2011

AbstractThe strain inhomogeneity and crystallographic domain structures and their influence on the electrical transport and magnetic properties of epitaxial colossal magnetoresistive La1-xCaxMnO3 (x = 0.2, 0.33) films have been studied as a function of film thickness and two types of (001) substrates, SrTiO3 and LaAlO3. Out-of-plane and in-plane lattice parameters were determined using normal and grazing incidence x-ray diffraction (GID), and least-squares fits of off-axis x-ray reflections. The lattice strain near the film surface as determined by GID appears to relax faster than that at the film interior as determined by the least-squares fit, indicating the presence of strain inhomogeneity in the films. The observed strain inhomogeneity appears to influence the magnetic and electrical transport properties. In particular the measured temperature dependent magnetization exhibits multiple transitions indicating a variation of Curie temperatures within the same sample. While the very thin films exhibit single out-of-plane domains, accompanied by a high crystalline coherence and smooth surfaces, strain relaxation in thicker films leads to mixed ( 001)T and (110)T textures, and increased mosaic spread and surface roughness. The films also exhibit electrically insulating “dead” layers about 100 – 200Å thick.
Computation of Optical Properties for Quantized Electronic Systems
Authors: Jacobs V. L. 
Published: April 2011

ABSTRACTA density-matrix description has been developed to treat relaxation (decoherence) phenomena during resonant and non-resonant radiative transitions of quantized electronic systems, including many-electron atoms and quantum-confinement systems (e. g., semiconductor microstructures). Radiative and collisional relaxation phenomena have been treated using Liouville-space proj ecti on-operator techniques. Both time-independent (resolvent-operator) and time-dependent (equation-of-motion) formulations have been developed. The self-energy operators that occur in these formulations can provide the fundamental basis for a self-consistent determination of the non-equilibrium and coherent electronic-state kinetics together with the homogeneous spectral-line shapes. This density-matrix description can be adapted for the computer simulation of electromagnetic processes. From first-principles electronic-structure calculations or from semi-empirical approaches, the parameters describing the elementary collisional and radiative interactions can be evaluated and organized into the basic data set for the application of the density-matrix description. The final product is a theoretical prediction for the linear or non-linear optical absorption or emission spectrum corresponding to a given set of values for the appropriate physical variables, such as temperatures, densities, and electric or magnetic field strengths.
Theoretical and Experimental Analysis of the Low Dielectric Constant of Fluorinated Silica
Authors: Demkov A. , Liu R. , Zollner S. , Werho D. , Kottke M. , Gregory R.B. , Angyal M. , Filipiak S. , Mcintyre L.C. , Ashbaugh M.D. 
Published: April 2011

ABSTRACTFluorinated silica has a dielectric constant E in the range of 3—3.5, lower than that of F-free SiO2 (ω=4). The reasons behind this reduction are controversial. It is not known whether the electronic or ionic contributions to the overall screening are being diminished upon F doping. To shed more light on this phenomenon we have studied F-doped SiO2 with ab-initio modeling and various characterization techniques. FTIR transmission and spectroscopic ellipsometry give us information about the ionic and electronic contributions to ω Nuclear reaction analysis and Auger spectrometry measure F composition. XPS and FTIR provide information on the atomic structure and stability of the film. We use a large cell of cristobalite to model fluorinated silica theoretically. The ground state geometry is obtained via energy minimization. We calculate the vibrational density of states and find a localized mode (Si-F stretch), in good agreement with FTIR transmission. We analyze the effects of F incorporation on the dielectric properties.
Fiber Bragg Grating Growth Simulation Using an Inverse Scattering Matrix Approach
Authors: Manca A. , Anedda A. 
Published: April 2011

ABSTRACTFiber Bragg gratings are playing an important role in the field of optical telecommunications and sensors. We have simulated the growth of gratings, longitudinally written in the core of germanosilicate optical fibers by an Ar+ laser. Following a Kramer-Kronig model, absorption in the Germanium Oxygen deficient centers band (∼240 nm) is considered to be responsible for the fiber photosensitivity and a two photon absorption process models the dynamics of the refractive index variation.The spatial propagation of light along the grating is described by the coupled wave theory and is calculated by using an inverse scattering matrix technique. The predicted physical properties of the gratings, reflectivity and temporal dispersion of propagating light as a function of wavelength and input power, show that a sustained growth is possible. A good agreement with previous simulations and experiments is found.