bluuebunny/crossref_metadata_2025_split huggingface dataset:
Silicon-On-Insulator Mosfets Fabricated in Zone-Melting-Recrystallized Poly-Si Films on SiO2
Authors: Tsaur B­Y. , Gels M. W. , Fan John C. C. , Silversmith D. J. , Mountain R. W. 
Published: March 2011

ABSTRACTN- and p-channel enhancement-mode MOSFETs have been fabricated in Si films prepared by zone-melting recrystallization of poly-Si deposited on SiO2-coated Si substrates. The transistors exhibit high surface mobilities, in the range of 560–620 cm2/V−s for electrons and 200–240 cm2/V−s for holes, and low leakage currents of the order of 0.1 pA/μm (channel width). Uniform device performance with a yield exceeding 90% has been measured in tests of more than 100 devices. The interface between the Si film and the SiO2 layer on the substrate is characterized by an oxide charge density of 1–2 × 1011 cm−2 and a high surface carrier mobility. N-channel MOSFETs fabricated inSi films recrystallized on SiO2-coated fused quartz subtrates exhibit surface electron mobilities substantially higher than those of single-crystal Si devices because the films are under a large tensile stress.
P-Glass Reflow with a Tunable CO2 Laser
Authors: Jeuch P. , Joly J.P. , Hode J.M. 
Published: March 2011

ABSTRACTPhosphosilicate glass reflow to improve step coverage of metallizations in integrated circuits is usualy made by a high temperature heat treatment. A new technique is proposed to achieve this annealing by a transient localized heating with a tunable CW CO2 laser. A selective coupling of the laser power is obtained by choosing a 9.25 μm wavelength which matches the Si-O absorption band at 1100 cm−1. Focusing and scanning the laser beam makes the P-glass flow without excessive substrate heating.
Laser–Assisted Mos/Sos Transistor Fabrication
Authors: Hess L.D. , Kokorowski S.A. , Olson G.L. , Chi Y.M. , Gupta A. , Valdez J.B. 
Published: March 2011

ABSTRACTCW laser annealing techniques were incorporated into standard MOS/SOS transistor fabrication procedures and found to be advantageous as compared to conventional furnace methods for electrical activation of ion–implanted source/drain dopants for both N- and P–MOS transistors. Static electrical characteristics of 2.4 μm channel–length transistors are similar for both types of annealing, whereas the speed of devices with cw laser annealed source–drain regions is increased 10 to 40%, depending on the operating voltage.
Formation of p-n Junctions by Laser Processing Sb-Pt Thin Films on Si
Authors: Schutz R. J. , Celler G. K. , Chang C. C. 
Published: March 2011

ABSTRACTPlanar p-n junctions with Pt silicide contacts have been formed by laser irradiating p-type Si/120Å Sb/400Å Pt composite thin film structures. The samples were prepared in a standard e-beam evaporation system. They were never ion implanted. Laser processing was performed with either a scanning cw Ar laser or a Q-switched Nd:YAG (λ = 0.53 μm) laser which provided 100 nsec long pulses. After the irradiations were performed, a p-type Si/n+Si/Pt-Si structure was present. The n+ region resulted from Sb incorporated in the Si lattice. When the same initial composite was furnace annealed, the Sb diffused to the surface and sublimated, leaving a p-type Si/PtSi near-ohmic contact. Depth profiles of the samples were determined with Auger electron spectroscopy. The structure of the Pt-Si layer was studied using wide film Debye X-ray diffraction. The electrical properties of the junctions were examined by measuring their I-V and C-V characteristics and minority carrier lifetimes. Differences in the structural and electrical properties that resulted from the two types of laser irradiation will be discussed.
Surface and Subsurface Morphology of Laser Bean Annealed Auge/Gaaa Ohmic Contacts
Authors: Aina O. , Norton J. , Katz W. , Smith G. , Rose K. 
Published: March 2011

ABSTRACTA study of the pulsed laser annealing of AuGe films on GaAs using a Nd:YAG laser has revealed differences between the surface and subsurface morfhologies. At laser energy densities lower than 1.1 J/cm2 , the surface retained the smooth, “golden” appearance of deposited AuGe films, while evidence of damage was observed below the surface. At higher energy densities, surface damage was observed. SIMS profiles of Ga and As in the AuGe layer and a laser heating model have been used to explain the presence or absence of damage in terms of the outdiffusion of As and Ga through the laser created melt which leads to the presence or absence of Ga and As at the surface and below the surface.
Laser Annealing of Selenium Implxnted InP
Authors: GILL Sukhdev , Topham Peter , Sealy Brian , Stephens Kenneth , Hales Michael 
Published: March 2011

ABSTRACTWe have compared the electrical properties of laser and furnace annealed selenium implanted InP. Both annealing methods produce high activities, the best being for anneals in a phosphine ambient which also produces a better surface finish. Reasons for the poorer results from the laser annealed samples have been deduced from Rutherford backscattering experiments.
Transient Infrared Reflection and Transmission of Silicon During Pulsed Laser Annealing
Authors: Moss Steven C. , Marquardt Charles L. 
Published: March 2011

ABSTRACTWe report measurements of reflectivity and transmission of probe beams at 0.633, 1.06, 1.34, and 3.39 μm during pulsed laser annealing of silicon. The transient infrared optical response of the silicon was monitored with several fast photodetectors. The diversity of detector response to transmitted light indicates that contradictory results obtained previously may be artifacts of photodetector response.
Discharge Annealing of Ion Implanted Silicon
Authors: Fleddermann C. B. , Ianno N. J. , Verdeyen J. T. , Streetman B. G. 
Published: March 2011

ABSTRACTA gas discharge system is used to produce a large area electron beam which can be used to angeal ion-implanted semiconductors. The sample temperature rise and amorphousto-single-crystal regrowth were monitored using the change in optical reflectivity.
Picosecond Dynamics of Laser Annealing
Authors: Kim Dae M. , Shah Rajiv R. , Von Der Linde D. , Crosthwait D.L. 
Published: March 2011

ABSTRACTWe report simultaneous measurements of time resolved reflection and transmission of low intensity 1.06 μm, 35 ps pulses subsequent to excitation of 50 KeV, 1016 cm−2 boron implanted silicon by 0.53 μm 35 ps pulses of varying energy densities. The samples are examined by optical and scanning electron microscopy in conjunction with defect etching. These data are discussed from the point of view of both the thermal melting model and plasma model.
On the Mechanics of Failure in Ceramic/Metal Bonded Systems
Authors: Evans Anthony G. , Ruhle M. 
Published: March 2011

AbstractStress concentrations that develop in metal/ceramic bonded systems have been evaluated and shown to encourage crack propagation at, or near, the edge of bonded interfaces. Experimental indentation observations on Nb/Al2O3 confirm the existence of the predicted stress concentrations. In this system, failure was invariably observed to initiate in the ceramic, such that quasi-static cracks located at the interface exhibited crack blunting. However, substantial dynamic reductions in the crack growth resistance of the interface are inferred from fracture surface observations. Implications for the optimal strengths of ceramic/metal bonded systems are presented.
Thermal Expansion Mismatch in Electronic Packaging
Authors: Carlson R. O. , Glascock H. H. , Webster H. F. , Neugebauer C. A. 
Published: March 2011

AbstractThermal expansion mismatch causes serious problems in operating device reliability because of the various stresses imposed on the joint materials undergoing temperature changes. Silicon has a low expansion coefficient so strain buffers are often employed between the silicon and the outer metal covers with relatively high expansion coefficients. These buffers can be metals like molybdenum, ceramics like alumina, or a brush structure of copper, with soft solders at the joints. However, solders themselves have finite fatigue lives which can be estimated from material and dimensional data.
An Overview of Materials Science in Printed Circuit Packaging
Authors: Seraphim D. P. , Lee L. C. , Appelt B. K. , Marsh L. L. 
Published: March 2011

AbstractA brief description of a set of processes and materials to make printed circuit panels will be given. Then we will discuss the multi-disciplines required for forming a scientific base and provide examples where the fundamentalist and often times specialist is providing the scientific data needed by the packaging engineer. Control techniques, characterization or otherwise basic information helpful in decision making is provided to the development and production groups. Specifically, the state of resin cure at critical steps in the process is used to demonstrate the inter-relation between cure, flow, and mechanical properties in affecting printed circuit board integrity. Finally, the complex role of moisture solubility and diffusion from the process environment in perturbing the chemical and mechanical state is discussed.
Chemical Interactions at Metal-Polymer Interfaces
Authors: Hahn P. O. , Rubloff G. W. , Bartha J. W. , Legoues F. , Tromp R. , Ho P. S. 
Published: March 2011

AbstractThis paper summarizes recent studies on metal-polymer interfaces for Cu, Ni and Cr on a high temperature polymer, polyimide. First some surface and bulk chemical properties of polyimide are described briefly, as measured with surface spectroscopies and verified by theoretical molecular orbital calculations. Then the chemical bonding and reactivity of the three interfaces are described and discussed in light of experimental observations of electronic structure, composition and interface morphology. The chemical trend of increasing reactivity of the interface is illustrated by comparing results from Cu to Cr.
Ion Beam Analysis of Diffusion in Polymer Melts
Authors: Green P. F. , Mills P. J. , Palmstrom C. J. , Mayer J. W. , Kramer E. J. 
Published: March 2011

AbstractTwo ion beam depth profiling methods have been used to measure the diffusion of polymer chains of molecular weight M into a matrix of polymer of molecular weight P. In the first the displacement xm of Au markers at the original interface of a diffusion couple between polystyrene with P=2×107 and a thin film of PS with M<P is measured using Rutherford backscattering spectrometry. From this modern version of the Kirkendall effect we find x=0.4t8(D*t) 0 5, where D* the tracer diffusion coefficient of the M chains at 174°C, is found to be D*=O.007M−2cm2/sec, in good agreement with the D*=DR expected for the reptation mechanism. Forward recoil spectrometry, a technique in which the energies of recoiling deuterons are detected, is used to obtain concentration profiles, and hence D*, of deuterated PS M-chains diffusing into a hydrogenated PS P-chain matrix. When P>>M, D*=0.008M−2, in good agreement with the marker data. When P<P*(M) however D*; increases greatly as P decreases; P* increases slowly with increasing M. The results are predicted quantitatively by D*=DR+DCR, where DCR=0.10Me2/(Mp 3 ) describes the diffusion of the M-chain by release of its topological constraints (by diffusion of the surrounding P-chains) and Me is an entanglement molecular weight. D* for self-diffusion (M=P) is dominated by reptation except for M's close to Me.
Electronic Structure and Properties of Oxide Surfaces and Interfaces
Authors: Stoneham A. M. , Tasker P. W. 
Published: March 2011

AbstractMany technologically-important areas rely on properties of ceramic surfaces or interfaces. Some of these properties are simply stability, e.g. resistance to dimension change, to grain-size change, or to change in coverage by a metal layer. Other properties rely on well-defined electronic features, e.g. a suitable density of surface states, of surface defects, or of response to adsorbed species. Still further surface characteristics - the precise geometric structures, the near-surface electric fields, and especially impurity segregation - can strongly influence observed behaviour.This survey emphasises the insights gained from atomistic modelling of ceramic surfaces and interfaces. The theoretical methods allow one to identify the features determining surface geometry, the degree of surface segregation by impurities, the role of the image charge and the influence of space-charge layers on intrinsic defect levels. The surface distortion affects defects like the surface Fs+ centre (electron trapped at an oxygen vacancy on an oxide) and similar colour centres. Whilst most of the results will be for oxides, parallels with semiconductor systems and the special features of metal-oxide interfaces are mentioned.
Characterization of Copper-Ceramic Interfaces
Authors: Kriven W. M. , Risbud S. H. 
Published: March 2011

AbstractThe interfacial zones in copper-magnesium aluminosilicate materials were characterized by several microscopic and microchemical techniques. Interfaces between copper-glass, copper-partially crystallized glass, and copper-fully crystallized glass were studied with the specific goal of determining the oxidation state of copper in various locations in the microstructure of the reaction zones. Optical microscopy, cathodoluminescence, electron probe microanalysis (EPMA), SEM, TEM, and other microtechniques were used. The presence of copper in various oxidation states can be attributed to the thermodynamics and kinetics of the system. Results correlating the observed interfacial microstructure and the thermochemistry of the system are presented.
Oxidation of Au/Si Films For Self-Confined Interconnects
Authors: Hewett C. A. , Scott D. M. , Lau S. S. , Bartur M. 
Published: March 2011

AbstractWe have explored the possibility of oxidizing a Au/Si composite layer or a Au-Si alloyed layer on SiO2 substrates to form a highly conductive narrow line with a protective SiO2 layer over it. A number of sample configurations and annealing ambients have been investigated. It was found that co-evaporated Au-Si alloys ( ∼30 at. % Au) showed no oxide formation for annealing temperatures between 200°C and 800°C in a flowing O2 ambient (annealing time ≃ 2.25hrs). Samples with a configuration of SiO2/Au/Si showed mixing of the Au and Si layers, but no appreciable oxide formation until after annealing at 800°C in a flowing O2. Samples with a configuration of SiO2/Si/Au, however, showed uniform and smooth oxide growth on top of the Au layer after annealing in air at 200°C. The structural and electrical properties of the self-confined Au lines will be discussed. This process may be potentially useful for narrow interconnects on VLSl chips.
Ceramic Substrates - Micro Circuits, a Partnership in Growth
Authors: Flock William M. 
Published: March 2011

AbstractAn increased understanding and utilization of suhstrate properties will he required to improve future performance and reliability of microelectronic devices. Previously, only the passive substrate/package properties were required for micro devices. Newer designs are utilizing both the active and passive properties of the ceramic materials. These new demands are being driven by end user circuit needs, and will generate major changes in the processing and fabrication of oxide materials.The status of oxide raw material availability, and the characterization of these materials is reviewed. The processing, and fabrication of substrate materials and the interactions with end use properties are discussed. The future expectations and demand on the materials and processes are forecasted. Substrate properties and their impact on final circuit performance are emphasized.
Tape Casting of BaTiO3
Authors: Blum J. B. , Cannon W. R. 
Published: March 2011

AbstractFor the past two years we have been investigating the tape casting of BaTiO3 Specifically we have been interested in developing a useful tape casting formulation and procedure and in studying the effects of powder particle size distribution and dispersion processes on the forming of BaTiO3 tapes.The formulation we have developed is non-aqueous. An MEKethanol mixture is the solvent and an acrylic binder is used. Two dispersants are being used, a phosphate ester and Menhaden fish oil. Ultrasonic dispersion was found to be effective in breaking up weak powder agglomerates. We have found it important to add the dispersant before adding other organic components to obtain the best dispersion and strongest tapes. The drying method is also important to tape strength. The strongest tapes resulted when the tape was removed from the glass plate soon after casting. We have also demonstrated that for forming purposes a wide particle size distribution is preferred.
Adsorption and Ordering of Oxygen on Cu(110)
Authors: Gruzalski G. R. , Zehner D. M. , Wendelken J. F. 
Published: March 2011

AbstractXPS and LEED were used to study the adsorption and ordering of oxygen on Cu(11O) at 83±1 K and between 300 and 320 K and to follow changes in the oxygen coverage and surface structure produced by 5-min anneals at temperatures up to 880 K. The relationship between oxygen coverage and surface structure, as well as their mutual dependence upon exposure, surface temperature at exposure, and subsequent annealing treatment, is discussed.
Studies of Planar Defects in Silver Plate-Like Crystals by CBED and Hrtem Techniques
Authors: Tanaka N. , Cowley J. M. 
Published: March 2011

AbstractElectron diffraction patterns with <111> incidence of f.c.c. plate-like crystals prepared by gas evaporation technique show forbidden spots such as the 1/3.422 spot. The origin of the spots has been explained in terms of planar defects such as (i) fractional unit cells on (111) surfaces, (ii) repeated thin twins and (iii) stacking faults or hexagonal layers. In the present study, the defect structures are examined by CBED and HRTEM techniques. The <111> CBED pattern of the platelet shows three-fold symmetry for the whole pattern. The dark field patterns of ± 1/3. 422 discs show symmetry of. These features prove that the platelet ha-s no center of symmetry for the three dimensional crystal (3m) and irregular arrangements of twins parallel to (111) planes. The electron micrographs taken along the <110> and <211> directions can give “cross-section” images of the platelet. The images show a few repeated twins with a thickness of several nm. The dark field images taken with the forbidden spots with <111> incidence show weak step contrast. The contrast may be due to fractional unit cells. Consequently, the forbidden spots of the platelet are mostly due to the fractional unit cells.
Analysis of the Structure of Grain Boundaries Normal to the Boundary Plane Using Diffraction Techniques
Authors: Vaudin M. D. , Schmückle F. , Lamarre P. A. , Sass S. L. 
Published: March 2011

AbstractBy recording the intensity of electron scattering along the reciprocal lattice direction normal to the interface plane of a grain boundary, diffraction data is obtained which is sensitive to the boundary structure along this direction. Kinematical calculations of the diffracted intensity profile normal to the interface show that such diffraction data can provide information on the local expansion at the interface and the rigid body translation between the two grains. Electron diffraction data obtained from a variety of different boundaries are presented and analyzed by comparison with intensity profiles calculated for various model boundary structures.
Local Atomic Structure and Electrical Activity of Arsenic Implanted in Silicon
Authors: Erbil A. , Cargill G. S. , Boehme R. F. 
Published: March 2011

AbstractWe summarize the results of an extensive investigation on ion implanted arsenic in silicon after pulsed laser annealing and laser plus furnace annealing. The experiments are aimed at determining the structural and chemical environment around an arsenic impurity atom and relating that information to the electrical behavior of arsenic in silicon. We have implanted silicon with arsenic, 6×1016 As/cm2 at 100 KeV, followed by laser annealing, to obtain epitaxial regrowth with peak As concentrations of about 8 at.%. Subsequent furnace annealing at 800°C for 30 minutes reduces the apparent electrical activity of the arsenic atoms, increasing the electrical resistivity by a factor of three. We have used EXAFS, together with RBS and ion channeling, to investigate the structural and chemical origins of this deactivation. EXAFS measurements are consistent with As occupying tetrahedral sites in both laser ann-ealed and laser plus furnace annealed samples. Average As-As coordination numbers, found from fitting the EXAFS data, were 0.2 and 4.5 for nearest neighbors and for next nearest neighbors respectively. These coordination numbers suggest that there are regions with As concentrations much greater than the nominal maximum concentration mentioned above, and that the preferred local chemical order in regions of high As content resembles that in GaAs, with Si preferentially occupying Ga-sites. This short-range chemical order is unchanged by the furnace annealing. However, we find that furnace annealing does reduce the As-As second neighbor distance by approximately 0.1Å.
Damage Nucleation in Si During Ion Irradiation
Authors: Holland O. W. , Fathy D. , Narayan J. 
Published: March 2011

AbstractDamage nucleation in single crystals of silicon during ion irradiation is investigated. Experimental results and mechanisms for damage nucleation during both room and liquid nitrogen temperature irradiation with different mass ions are discussed. It is shown that the accumulation of damage during room temperature irradiation depends on the rate of implantation. These dose rate effects are found to decrease in magnitude as the mass of the ions is increased. The significance of dose rate effects and their mass dependence on nucleation mechanisms is discussed.
Characterization of Epitaxial CoSi2 Films Grown on <111> Si
Authors: Hamdi A. H. , Nicolet M-A. , Kao Y. C. , Tejwani M. , Wang K. L. 
Published: March 2011

AbstractX-ray rocking curves and backscattering spectrometry with channeling have been employed to investigate epitaxial CoSi2 films grown on <111> Si substrates. Several preparation techniques were used: sputter cleaning, chemical cleaning, chemical cleaning with subsequent high temperature annealing, and e-gun evaporation on a cold or hot Si substrate, in situ annealing between 550–750°C for 30 min. Best results were obtained with chemical cleaning and pre-annealing at 925°C for 10 min, Co and Si codeposition on a 580'C hot substrate. For such samples, a typical x-ray perpendicular strain is -2.08%, and parallel strain is -0.11%. This parallel strain implies that the growth has been accommodated by dislocations with a spacing of ,∼ 2000 Å. The values of strain are consistent with the published lattice constants of Si and CoSi2 and Poisson's ratio of 0.28. The minimum yield in the channeling spectra of these films is. ∼ 3.6%, which is only slightly higher than that of <111> virgin Si.
The Gamma to Alpha Transformation in Thin Film Alumina
Authors: Clausen E. M. , Hren J. J. 
Published: March 2011

AbstractMany forms of low temperature alumina have been identified [1]. These are collectively referred to as transitional forms. The particular form depends strongly on the starting material (e.g., hydrated, thermally oxidized, alkoxide, etc.), the impurities present, and on thermal history. Although different forms of transition alumina are sometimes referred to as phases, none can be considered a true polymorph of corundum, i.e., α-alumina. Transformations from one form to another which occur upon heating are not reversible, although they are quite reproducible [2]. These different transitional structures are therefore considered to comprise different states of reordering. Figure 1 is a compendium of powder x-ray diffraction patterns from all known transitional aluminas and several aluminum hydroxides [3]. It i.s obvious that there are several crystallographic spacings which are nearly common to all forms.