bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Characterization of New Cleaning Method Using Electrolytic Ionized Water for Poly Si Cmp Process
Authors: Miyashita N. , Uekusa Shin-ichiro , Seta S. , Nishioka T. 
Published: April 2011

ABSTRACTA Trench isolation technology has been developed and applied to high-speed bipolar LSI production. In general, the wafer surface after a conventional ploy-Si Chemical-Mechanical-Polishing (CMP) is contaminated with silica particles and chemical impurities. These contaminations produce some unexpected patterns and crystal defects in the wafer surface layer after oxidation. It is difficult to remove them by the conventional cleaning techniques. Therefore, we have established the new post CMP cleaning method, using the electrolytic ionized water containing chemical additive of a small quantity. The anode water has the cleaning effect for the metallic and organic contaminations, and the cathode water has the removing effect for the particles and the etching effect for the poly-Si surface. For this new cleaning process, it is important to avoid the chemical mechanical damages on the surface and to control the surface roughness. Our experimental work has been focused on the large numbers of the remaining particle and the surface roughness using a particle counter and an atomic force microscopy (AFM). We herein report the properties of the electrolytic ionized water and the examined results of poly-Si surface after CMP process. It was found that the electrolytic ionized water is effective for surface control, and the new cleaning process is useful for CMP process.
MOCVD ZnS:Mn Films: Grain Size Distribution and Crystal Structure as a Function of the Growth Parameters
Authors: Dunn Kathleen A. , Dovidenko Katharine , Topol Anna W. , Oktyabrsky Serge R. , Kaloyeros Alain E. 
Published: April 2011

ABSTRACTZinc sulfide doped with manganese is extensively used for thin film electroluminescent device applications. In order to assess the key material and process challenges, ZnS:Mn layers were fabricated by metalorganic chemical vapor deposition in the 250°-500°C range on an AlTiO/InSnO/glass stack. The microstructure of the ZnS:Mn films was examined by Transmission Electron Microscopy (TEM) as part of a larger study which fully characterizes these films by a variety of structural and chemical characterization techniques, including Rutherford Backscattering, Secondary Ion Mass Spectroscopy, Atomic Force Microscopy, Scanning Electron Microscopy and X-ray Diffraction. For all the growth conditions, the films were found to be polycrystalline having predominantly 2H hexagonal ZnS structure. The ZnS grains are found to grow columnar as the film thickness increases, also widening in the direction parallel to the substrate surface and reaching the 100 - 200 nm average lateral size at the 650 nm film thickness. The presence of the 8H ZnS polytype was detected in the low-temperature ZnS:Mn films by TEM selected area electron diffraction and confirmed by X-ray diffraction analysis. Dark field TEM imaging correlated this 8H ring with very small (∼2.5 nm) grains present throughout the low temperature film with a slightly higher density at the film/substrate interface. The 700°C post-deposition annealing was found to initiate a solid state transformation to the cubic (3C) ZnS crystal structure, and resulted in an average grain size of ∼250 nm at the surface of the annealed film.
Electrode Characteristics of Sputtered Lithium Manganese Oxide Films with Diamond-Like-Carbon Top Layer
Authors: Moon Hee-Soo , Ji Kwang-Sun , Cho Won-Il , Yun Young-Soo , Park Jong-Wan 
Published: April 2011

ABSTRACTThere have been increasing interests in lithium rechargeable batteries, especially microbatteries, with rapid development of portable electronic equipments and MEMS(Micro electromechanical systems) technology. In this work, lithium manganese oxide, as a strong candidate for the battery materials, which is more abundant, stable in ambient state and less toxic than the other oxides such as lithium nickel oxides and lithium cobalt oxides, was deposited by rf magnetron sputter. The effect of thermal treatment on the microstructure and electrode characteristics of lithium manganese oxide cathode was investigated. In electrochemical experiment using liquid electrolyte, half-cell failure would be caused by manganese dissolution, degradation of electrolyte materials during charging/discharging process and so on. In this research we focus on interface reaction problem that would affect the cyclability and lifetime of microbattery. In order to reduce the interface reaction during operation, we introduce DLC(Diamond-like-Carbon) film that has high electrical resistivity, mechanical hardness and chemical stability. DLC film was deposited on sputtered lithium manganese oxide electrode by ECRCVD(Electron Cyclotron Resonance Chemical Vapor Deposition). DLC-top-layer LiMn2O4 film was more stable during charging/discharging reaction and higher discharge capacity in wide voltage windows than LiMn2O4 film.
Have We Found The Final Explanation For The Onset Of Rapid Interlayer Mass Transport?
Authors: Giesen M. , Ibach H. 
Published: April 2011

ABSTRACTIn recent STM experiments on multilayer island decay on Cu(111) in UHV a novel rapid interlayer mass transport was observed. This new transport mechanism may accelerate island stack decay by several orders of magnitude. Initial explanations for the onset of rapid decay events were based on the correlation between the occupation of surface states and the presence of a step edge barrier for adatom hopping over the island edges. We present new experimental data measured for Ag(111) which are in contradiction to the former interpretation of rapid interlayer mass transport. We show that all experimental results may be explained by considering an exchange mechanism when island edges in a stack are in close proximity.
The influence of the internal microstructure on the surface parameters of polycrystalline thin films
Authors: Eisenmenger-Sittner C. , Bergauer A. 
Published: April 2011

ABSTRACTPhysical Vapor Deposition (PVD) processes commonly lead to the formation of polycrystalline thin films due to the effects of island nucleation and growth. Scanning probe Methods such as Atomic Force Microscopy (AFM) or Scanning Tunneling Microscopy (STM) are widely used for the characterization of the film surface. The topographic data obtained from these measurements can be converted to roughness values, Power Spectral Densities (PSD's) or correlation functions.It is the objective of this paper to evaluate the possibilities to characterize the polycrystalline template which generates the film surface solely by quantities derived from topographic data. For this purpose roughness values, PSD's and correlation functions of polycrystalline Al-Films deposited on glass substrates and from simulated surfaces are compared. The main factors which influence the shape of PSD's and correlation functions are determined and possible connections between the constitution of the polycrystalline template (e. g. shape and size-distribution of the crystalline domains) and the film roughness are discussed.
Nanoindention studies of DC sputtered Cu and Cu/Cr thin films
Authors: Wei G. , Du J. , Rar A. , Barnard J. A. 
Published: April 2011

ABSTRACTThe nanoindentation behavior of DC magnetron sputtered 10 nm Cu and 10 nm Cu/2 nm Cr thin films deposited on Si (100) has been studied using a Hysitron nanomechanical system. X- ray diffraction and X-ray reflectivity were used to measure the film structure and film thickness, respectively. The grain size and orientation of Cu and Cu/Cr thin films were measured by TEM. Atomic force microscopy (AFM) was used to evaluate the surface morphology and roughness. At the same load, the nanoindentaion displacement of Cu/Cr is smaller than that for Cu, i.e., the 2nm thick Cr underlayer enhances the hardness of Cu. X-ray, TEM, and AFM results show that the grain size of Cu/Cr (< 15 nm) is actually larger than Cu (∼ 3 nm) indicating that the inverse Hall-Petch relationship may be operative.
Nucleation and Growth During Tungsten Atomic Layer Deposition on Oxide Surfaces
Authors: George S. M. , Elam J.W. , Grubbs R.K. , Nelson C.E. 
Published: April 2011

ABSTRACTNucleation and growth has been studied during tungsten (W) atomic layer deposition (ALD) on oxide surfaces. Auger electron spectroscopy (AES) was utilized to examine the deposition of W during the sequential (A) WF6 and (B) Si2H6 reaction cycles that define W ALD. The AES results displayed an initial nucleation period of ∼10 AB cycles to deposit one tungsten monolayer on SiO2. Subsequently, the W and Si AES signals grew and oscillated dramatically versus WF6 and Si2H6 exposures. The increase in the W AES signal in the growth region was consistent with a W ALD growth rate of 3.5 Å per AB cycle. An examination of the oxygen and tungsten AES signals versus AB cycles indicated that W ALD displayed nearly ideal “layer-by-layer”, Frank- van der Merwe growth after the nucleation period. On Al2O3, the AES results displayed a much shorter nucleation period for W ALD. Only 3 AB cycles were required to deposit one tungsten monolayer. Subsequently, the tungsten film grew at a rate of 3.6 Å per AB cycle. The initial nucleation period and growth mechanism during ALD are important because they will affect the roughness of the resulting ALD film.
Apparatusdevelopment For Diamond Synthesis From Acetone Vapor with Low Energy Consumpution
Authors: Onishi Fumitomo , Hayashi Rie , Takagi Yoshiki 
Published: April 2011

ABSTRACTWe synthesized diamond via gaseous phase of vaporized acetone. Molecular acetone decomposes to two methyl radicals with thermal activation. We propose here a new method for diamond synthesis with these methyl radicals from molecular acetone. With this method, we successfully synthesized diamond particles with shorter experimental time than conventional method. With liquid carbon source, such as acetone, impurity elements will be easily substituted in synthesized diamond thin, film which has wide applications for the future electronic devices.
Reduction of Defect Density in Structures With InAs-GaAs Quantum Dots Grown at Low Temperature for 1.55 [.proportional]m Range.
Authors: Zakharov N.D. , Werner P. , Gösele U. , Ledentsov N.N. , Bimberg D. , Cherkashin N.A. , Bert N.A. , Volovik B.V. , Ustinov V.M. , Maleev N.A. , Zhukov A.E. , Tsatsul'nikov A.F. 
Published: April 2011

ABSTRACTTransmission electron microscopy (TEM), and photoluminescence (PL) have been used to evaluate defects and the efficiency of defect-reduction techniques in structures with InAs quantum dots (QDs) for the 1.55 µm range grown at low substrate temperature (LT) using molecular beam epitaxy (MBE). We show that capping of the QDs with thin GaAs layer accompanied by growth interruption at 600oC (flash) allows to eliminate large islands, containing dislocations, while the smaller islands containing local defects (e.g. dislocation dipoles) still remain. If the flash procedure is accompanied with further depositing of thin AlAs cap layer, and followed by high temperature (~700oC) annealing (HTA), an almost complete elimination of defects is observed. The structures emit in the range of 1.55 µm due to lateral agglomerates of LTQDs. Simultaneously bright luminescence due to isolated QDs and GaAs matrix are detected at high excitation densities.
Dielectric and Ferroelectric studies of Pb0.85La0.15TiO3Thin Films on solution derived RuO2Bottom Electrodes
Authors: Bhaskar S. , Majumder S. B. , Dobal P. S. , Krupanidhi S. B. , Katiyar R. S. 
Published: April 2011

ABSTRACTSol-Gel derived Pb0.85La0.15TiO3PLT15) thin films were deposited on solution derived RuO2/Si, RuO2/Pt/Si and Pt bottom electrodes. Dielectric, tangent loss, hysteresis, J-E, measurements were also carried out on these films. X-ray results established the single phase perovskite formation with no secondary phases of PLT15 thin film on these electrodes. PLT15 thin films on RuO2bottom electrode showed relatively inferior ferroelectric and dielectric behavior as compared to Pt electrode. Low leakage currents (10-8A/cm2at 10 kV/cm) and the observed J-E characteristics have been attributed to poor film-electrode interface. Observed electrical and dielectric properties have been correlated with the film-electrode interface. The interface characteristics were further augmented by depth profile analysis using Auger Electron Spectroscopy.
Magnetism of Cobalt Base Artificial Lattice Films
Authors: Masuda Masataka , Matsumoto Shun , Taka Kunihiko , Yoshitake Naoki , Hayashi Yasunori 
Published: April 2011

ABSTRACTThe Co/Pd and Co/Pd artificial lattice films have attracted much interest by their special magnetization properties. We discussed the effect of the Pt, Pd layer thickness on the magnetic anisotropy, and we showed the effect of the hydrogen ion implantation on the magnetic properties of multi-layered films. The Co/Pt and Co/Pd multi-layered films were formed on Si(111) substrates with molecular beam epitaxy. We did structure analysis, magnetic domain analysis and magnetic properties evaluation with XRD, MFM and VSM, respectively. Among the series of films of 0.4nm Co layer, XRD showed that the film of 1.0nm Pt layer had a highest periodicity and that they had (111) plane orientation completely. The magnetic domain size reduced with the increase of the thickness of Pt layer. We found out that the coercivity decreased linearly as a function of the length of magnetic domain wall in the unit area. The result of VSM showed that the multi-layered films of Pt thickness of less than 2.8nm had perpendicular magnetic anisotropy. The perpendicular anisotropy energy changed by the nonmagnetic layer thickness and had a maximum value for 0.4nm Co 0.4nm/ nonmagnetic metal 1.0nm multi-layered film. After hydrogen implantation into the films, XRD showed that the lattice spacing was swelled with hydrogen dose. Also, MFM observed that the magnetic domain size reduced with the increase of the hydrogen dose. The easy axis of magnetization changed from perpendicular to parallel in the plane with the increase of the hydrogen dose. After evacuation of hydrogen at 473K, perpendicular anisotropy was partially recovered. This phenomenon suggested that the origin of magnetic anisotropy was mainly the lattice mismatch and distortion in the layer interface. But Co/Pd film was not recovered by this thermal treatment. This means that Pd made stable hydride and did not evacuate hydrogen at this temperature.
Temperature Dependence of the Magnetoresistance of Co/Re Superlattices
Authors: Charlton Timothy , Lederman David , Felcher Gian P. 
Published: April 2011

ABSTRACTHcp (10.0) Co/Re superlattices were grown by dc magnetron sputtering on sapphire (11.0) substrates with the [00.1] direction of the superlattice in the film plane. The temperature-dependent magnetoresistance (MR) was measured on samples patterned by photolithography from 10 K to 300 K in a 5.5 T superconducting magnet. The pattern allows the measurement of the MR with the current (I) and the magnetic field (H) parallel or perpendicular to the magnetic easy axis (c, the [00.1] direction). Measurements at 5 K on an antiferromagnetically-coupled sample shows dips in the MR near H = 0 when H ∕∕ c and H ⊥ I, dips below the saturation value at H ∼ 2.5 kOe for H ∕∕ c and H ∕∕ I configuration due to the competition between the anisotropic magnetoresistance (AMR) and the giant magnetoresistance (GMR). Since the AMR is dependent on the transport within the ferromagnetic layers, the temperature dependence yields information about the relative magnitudes of interface vs. bulk spin-dependent scattering. Our analysis shows that the GMR is anisotropic and that the spin-dependent scattering occurs predominantly at the interfaces only for certain configurations.
Magnetostriction and Microstructure of As-Deposited and Annealed Co Thin Films
Authors: Brückner Winfried , Hecker Michael , Thomas Jürgen , Tietjen Detlev , Schneider Claus M. 
Published: April 2011

ABSTRACTThe magnetostriction of as-sputtered and annealed 400 nm thick Co films has been studied in longitudinal and transverse magnetic fields. The appreciable change of the magnetostriction behavior after annealing above 250 °C is correlated to grain growth and to the related change of the texture (from nearly randomly distributed hcp-Co crystallites to a c-axes texture perpendicular to the film plane). The magnetostriction behavior in the annealed samples cannot be explained by a domain magnetization within the film plane. It is assumed that a rotation of the spontaneous magnetization out of the film plane occurs due to the development of a perpendicular magnetic anisotropy.
Co/Pd Multilayer Based Recording Layers For Perpendicular Media
Authors: Litvinov Dmitri , Roscamp Thomas A. , Klemmer Timothy , Wu Mei-Ling , Howard J. Kent , Khizroev Sakhrat 
Published: April 2011

ABSTRACTThe results of the experimental study of CoX/Pd multilayer based recording layers for perpendicular recording media are presented. The perpendicular magnetic recording media with multilayer recording layers and high moment soft underlayers were deposited by magnetron sputtering. It is shown how a favorable microstructure of the multilayer films can be achieved by the use of the appropriate buffer layers. The effects of boron addition to the cobalt layer in a multilayer recording layer is described. The feasibility of the aging process that leads to the reduced exchange coupling in the multilayer recording layer, is demonstrated. It is shown that boron addition to the cobalt layer accelerates the aging process.
Ferromagnetic and Structural Properties of Mn-Implanted p-GaN
Authors: Theodoropoulou N. , Hebard A.F. , Overberg M.E. , Abernathy C.R. , Pearton S.J. , Chu S.N.G. , Wilson R.G. 
Published: April 2011

ABSTRACTHigh doses (1015 – 5×x1016 cm−2) of Mn+ ions were implanted into p-GaN at ∼350oC and annealed at 700-1000°C. At the high end of this dose range, platelet structures of GaxMn1−xN were formed. The presence of these regions correlated with ferromagnetic behavior in the samples up to ∼250K. At low doses, the implantation led to a buried band of defects at the end of the ion range.
Electrochemical Deposition of FeCo Alloys and FeCo/TiO2 Nanocomposites
Authors: Shao I. , Vereecken P. M. , Cammarata R. C. , Searson P. C. , Chien C. L. 
Published: April 2011

ABSTRACTElectrochemical deposition of FeCo alloys with 1:1 atomic ratio has proved difficult due to cracking from high stress. By using a sulfamate electrolyte and optimizing other deposition parameters, we successfully electrodeposited high quality FeCo films of 20-25 mm in thickness and 7 mm in diameter. Using a suspension of hard oxide nanoparticles (25 nm TiO2) in the electrolyte, we produced oxide-dispersion-strengthened FeCo/TiO2 nanocomposite films with large grains. Enhanced strength was observed from these nanocomposites relative to pure FeCo alloys as determined from Knoop hardness measurements. In order to further improve the ductility of the alloys, vanadium has been codeposited with FeCo. Some preliminary results of FeCoV alloy deposition are reported.
High Strength Soft Magnetic Composites
Authors: Yu Ronghai , Corte-Real Michelle M. , Gorea Adrian , Ren Libo , Parvizi-Majidi Azar , Xiao John Q. 
Published: April 2011

ABSTRACTThere has been an increasing demand for high temperature soft magnetic materials with mechanical properties better than those of existing commercial materials such as FeCo alloys. We have designed new magnetic composites by reinforcing FeCo alloys with high strength tungsten fibers. The composite materials were fabricated by electrodeposition. In general, the as-deposited composites have a relatively high coercivity Hc and low magnetic permeability μ, because of induced strain during fabrication. After appropriate thermal annealing, the composites have good soft magnetic properties, comparable to commercial bulk alloys. However, the saturation induction is reduced due to the non-magnetic inclusions. The composites also show significant enhancements in yield strength and tensile strength that increases linearly with fiber volume fraction as seen in other common composite materials. In addition, near zero creep is observed at 600 °C under a stress of 600 Mpa. The mechanical properties can be further improved by co-depositing soft magnetic material and Al2O3 onto the fibers. An approximately linear relationship was observed between the coercivity and volume fraction of Al2O3 particles. The square-root relationship was observed between the hardness and the Al2O3 concentration.
Magnetic Properties of Transition Metal-Dendrimer Nanocomposites
Authors: Fry Richard A. , Shull Robert D. , Uppuluri Srinivas , Balogh Lajos 
Published: April 2011

ABSTRACTMagnetic nanocomposites have been successfully prepared by encapsulating nanosized entities of iron, cobalt, and nickel compounds in poly(amido-amine) (PAMAM) dendrimer hosts. Problems related to the instability of the magnetic structures under the influence of an external electromagnetic field have been overcome by using a solid polystyrene matrix to embed the dendrimer hosts containing the magnetic guests. SQUID magnetometry measurements on these nanocomposites showed that after subtraction of the diamagnetic polymer background, at 300 K all samples exhibited paramagnetic behavior, with susceptibilities of 1.14, 1.68, and 0.70 × 10−6 m3/kg for Fe-, Co-, and Ni-containing samples respectively. The temperature dependence for T<300 K showed typical paramagnetic behavior, with the susceptibility increasing for decreasing temperatures. Curie-Weiss (1/M vs. T) graphs displayed a linear behavior at high temperatures, with temperature axis intercepts (θ) occurring at –139 K (Fe), –16 K (Co), and 0 K (Ni). Negative deviations from Curie-Weiss behavior occurred at T<175 K for the Fe and T<25 K for the Co samples. Magnetic moments calculated from the high temperature Curie constant indicated that Fe, Co, and Ni possessed effective moments of 3.5, 4.4, and 2.8μB. The negative intercepts and the fact that these moments are larger than those expected for metallic transition metals are indicative that these species are probably present in an oxidized form. The low-temperature behavior indicates either superparamagnetic or soft ferromagnetic behavior.
Hybrid High-Temperature Nanostructured Magnets
Authors: Sellmyer David J. , Zhou J. , Tang H. , Skomski R. 
Published: April 2011

ABSTRACTThe hysteretic behavior of two-phase permanent magnets for high-temperature applications is examined. A variety of systems have been synthesized and investigated, including Sm-Co-Cu-Ti bulk magnets, SmCo5:Cu-Ti thin-film materials, and mechanically milled Sm-CoZr magnets. The hybrid character of the material leads to very high room-temperature coercivities, between 30.2 and 43.6 kOe, and to the survival of a comparatively large part of the coercivity at high temperatures (12.3 kOe at 500 °C for SmCo 6.5Cu0.8Ti0.3). The coercivity reflects the structure and chemical composition of the material. When ferromagnetic grains are separated by a ferromagnetic boundary phase, the boundary phase acts as a pinning center, but when the grain-boundary phase has a comparatively low Curie temperature, the high-temperature magnetism of the system is that of a weakly interacting ensemble of magnetic particles. In spite of some residual paramagnetic exchange coupling, which is discussed in this work, this mechanism enhances the coercivity.