bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical Modeling of Energy-Beam Induced Localized Melting of Thin SI Films
Authors: Im J.S. , Lipman W J.D. , Miaoulis I.N. , Chenb C.K. , Thompson C.V. 
Published: March 2011

ABSTRACTWe have developed a quantitative model, based on a two-dimensional finite difference enthalpy method, which accounts for the localized melting behavior of thin Si films on substrates. The model incorporates radiative and conductive heat flow components and takes account of the phase changes that occur during zone-melting recrystallization. Emphasis is placed on the effects resulting from the differences in reflectivity and emissivity between solid and liquid Si. The model provides quantitative information concerning the temperature profile of the Si film and the configuration of the solid-liquid interface. Results of the analysis indicate that there exist two distinct types of transition behavior: i) reflectivity-change dominated and ii) emissivity-change dominated. Partial melting and a nonplanar solid-liquid interface are characteristics of the reflectivity-change dominated behavior. The emissivity-change dominated behavior, on the other hand, can be characterized by explosive-like melting and a planar solid-liquid interface. The conditions and physical factors which give rise to these behaviors are discussed.
Qualitative Model for Surface Rippling of Zone Melting Recrystallized Silicon-on-Insulator Layers
Authors: Mertens Paul W. , Maes Herman E. 
Published: March 2011

ABSTRACTIn zone melting recrystallization (ZMR) of thin silicon films different mechanisms can lead to thickness variations of the obtained silicon film. In this paper we will concentrate on some of these phenomena. One is the large scale mass transport, which typically leads to a thinned region at the start of the ZMR process. Another one, which is to a certain extent related to the first one, is the typical ripple formation that occurs especially under conditions that are commonly referred to as “low thermal gradient” regime.
Structure of Amorphous A12O3 Produced by Ion Implantation
Authors: Mchargue C. J. , Sklad P. S. , Angelini P. , White C. W. , Mccallum J. C. , Perez A. , Marest G. 
Published: March 2011

ABSTRACTThe amorphous state can be produced in α-Al2O3 by ion beam induced displacements at 77 K or by displacements combined with chemical effects at room temperature. Progress toward understanding the amorphization process has been made from studies of the short-range order, electronic charge on implanted species, and the critical composition for amorphization. Results are presented for implantation of Al + O in the stoichiometric ratio, zirconium, iron, and tin.
Refractive Index Profiles of High Dose Ti Implanted Optical Waveguides in LiNbO3
Authors: Bremer T. , Ashley P.R. , Irmscher R. , Buchal Ch. 
Published: March 2011

ABSTRACTSingle crystalline substrates of LiNb03 have been implanted with 48Ti ions at 200 keV and doses up to 4 × 1017 cm−2. The implants have been performed at wafer temperatures of 77 K, 300 K and 620 K. Immediate subsequent processing at 1273 K in wet oxygen ambient led to good epitaxial regrowth at all doses, if sufficient time was allowed. The maximum observed extraordinary refractive index change after regrowth Δne=0.04, indicating a solubility limit of 3.3×l021 Ti cm−3 corresponding to 18 % of Nb5+ replaced by Ti4+.
Crystallization of Intrinsic Amorphous Layers Produced by Stoichiometric Implantation of Al and O Ions in A-Axis Oriented Al2O3 Single Crystals
Authors: Zhou W. , Cao D.X. , Sood D.K. 
Published: March 2011

ABSTRACTIsothermal annealing behaviour of intrinsic amorphous layers produced by stoichiometric implantation in a—axis oriented α—Al2O3 single crystals has been studied. The amorphous phase transforms directly to α—Al2O3 at a well defined planar interface which moves towards the free surface. The epitaxial growth slows down after initial rapid crystallization, indicating two separate regimes. The interface velocity shows Arrhenius behaviour in both regimes with activation energies of 0.6 and 0.08 eV respectively. There is an evidence for additional surface or random crystallization into κ or γ-Al2O3 phases within the first few nm on the surface, after prolonged annealing. These results are remarkably different from those reported previously for c–axis oriented Al2O3 crystals, showing the importance of substrate orientation during crystallization. A tentative model to explain the crystallization behaviour is discussed.
Characterization of B and N Implanted Fused Silica
Authors: Arnold G. W. , Brow R. K. , Carr M. J. , Barbour J. C. 
Published: March 2011

ABSTRACTThe implantation of B and N into fused silica can result in chemical incorporation into the glass with a consequent larger increase in refractive index than is possible due to volume compaction alone. B implantation produces anomalously large concentrations of oxygen-vacancy defects which aid in the establishment of B into a borosilicate layer. N implants can result in unreacted N accumulations in addition to N incorporated into a Si-oxynitride layer. The unreacted N can also be incorporated by implantation damage (e.g., Si, Ar, Kr)--before or after N implantation--which provides additional occupancy sites. These results are important with respect to the use of implantation-produced waveguides for optoelectronic devices.
Surface Reaction in NiO CoO MnO and FeO in the Electron Microscope
Authors: Buckett M. I. , Marks L. D. 
Published: March 2011

ABSTRACTElectron irradiation damage in the metal monoxide series of group Vll and VIII elements -NiO, CoO, MnO and FeO - has been investigated in the non-UHV electron microscope environment. NiO and CoO were also examined in the UHV environment. Each of these materials showed comparatively similar electron-stimulated oxidation of the surface in the non-controlled conventional HREM environment, at a vacuum level of approximately 10–7 Torr; while only ballistic damage was observed in both the NiO and CoO under UHV conditions.
Dual Implantations of Ti and C into Sintered Α-Sic and Hot Pressed Si3n4
Authors: Bhattacharya R.S. , Rai A.K. , Kung S.C. , Patrizio D. 
Published: March 2011

ABSTRACTDual ion implantations of Ti+ and C+ into sintered a-SiC and hot pressed SÌ3N4 have been studied by Rutherford backscattering spectroscopy (RBS) combined with plan/cross section view transmission electron microscopy (TEM). The samples were analyzed before and after annealing at 1200°C for 2 hours in a vacuum of 1x10-6 torr. The results were compared with single ion implantation of Ti+. RBS analysis showed that no oxidation occurred during annealing and Ti diffused toward the surface in both SiC and SigN^ Cross section TEM analysis revealed the formation of TiC precipitates in SiC due to both dual (Ti+ + C+) and single (Ti+) ion implantations. Precipitates were found to form in SÌ3N4 as well; however, because of very close proximity of observed d values with those of TiC, TiN and β-SiC, it was not possible to uniquely identify the chemical nature of these precipitates. Thermo-dynamic calculations were performed to explain the observed results.
Effects of O2 Ion Bombardment of Y-Ba-Cu-Oxide during Thin Film Growth
Authors: Metzger G. , Fleddermann C. B. 
Published: March 2011

ABSTRACTOxygen ion beam bombardment has been studied as a means for incorporating oxygen into thin films of Y-Ba-Cu-oxide either by enhancing the transport of oxygen to substrates during ion-beam sputtering, or by direct incorporation of oxygen with ion-assisted deposition. Optical emission spectroscopy was used to study the ion-beam bombardment of bulk superconducting targets as the oxygen content of the ion beam was varied. This study showed that oxygen did not directly combine with metallic elements in the target to increase the oxygen content of the stream of particles moving toward the substrate. Addition of a second ion beam directing oxygen ions toward the substrate during film growth caused large variations in the stoichiometry of the deposited films. At low oxygen ion currents, no increase in the oxygen content of the films was detected, while at relatively high currents, the oxygen incorporation increased. However, the sputtering of the metallic components of the film increased as the oxygen beam current increased, leading to very low growth rates.
Thermodynamic and Structural Properties of Mev Ion Beam Amorphized Silicon
Authors: Roorda S. , Sinke W.C. , Poate J.M. , Jacobson D.C. , Fuoss P. , Dierker S. , Dennis B.S. , Spaepen F. 
Published: March 2011

ABSTRACTThermodynamic and structural properties of amorphous Si (a-Si), prepared by MeV 28Si+-ion implantation are investigated by differential scanning calorimetry, Raman spectroscopy and X-ray diffraction. The influence of thermal annealing below 500 °C on a-Si is investigated with these different probes. The observed changes result from structural relaxation. Raman spectroscopy and X-ray diffraction show that structural relaxation is accompanied by changes in the average atomic structure.
Spatial Damage Distribution in Electron-Beam Processed Gaas-Algaas Heterostructures, Experiment and Theory
Authors: Smith Doran D. , Fink Tobin , Braddock W. D. 
Published: March 2011

ABSTRACTThe effect of electron beam irradiation on the transport properties of HEMT structures has been studied. The data is found to agree with a model containing no free parameters which predicts the spatial extent of the damage. As grown HEMT material was fabricated into Hall bars. The material was then characterized by measurement of 2D EG number density and drift mobility. The material was then irradiated at constant dose with electron energies between 2.5 and 20 keV. Damage was assessed by changes in the number density and mobility. The number density was essentially unchanged at all energies. No change in mobility occurred for 2.5, 15, and 20 keV, however, a decrease in the mobility occurred for energies from 5.0 to 12.5 keV. These results agree with our model of the electrons energy loss as a function of its path length. The defects are shown to be charged, and possible sources of the defects are discussed.
Changing the Structural State of Amorphous Silicon by Ion Irradiation
Authors: Roorda S. , Sinke W.C. , Poate J.M. , Jacobson D.C. , Dierker S. , Dennis B.S. , Eaglesham D.J. , Spaepen F. 
Published: March 2011

ABSTRACTIon beams of keV and MeV energies have been used to bombard amorphous Si (a-Si), which had previously been annealed (‘relaxed’). Analysis by Raman spectroscopy and differential scanning calorimetry shows that when 1 out of every 20 Si atoms is displaced by a nuclear collision, the a-Si returns to its unrelaxed state and cannot be distinguished from as implanted a-Si. Moreover, the kinetics of the heat release on annealing of similarly bombarded crystalline Si (c-Si) are qualitatively identical to those of structural relaxation in a-Si. This implies that the population of ion beam induced defects in a-Si is very similar to that in c-Si. It also shows that defect annihilation is an important ingredient in the mechanism of structural relaxation of a-Si.
As and B Ion Implantation Through Mo and into Mo-Silicide Layers for Shallow Junction Formation
Authors: Angelucci R. , Merli M. , Solmi S. , Armigliato A. , Gabilli E. , Govoni D. , Poggi A. 
Published: March 2011

ABSTRACTGood quality p+/n and n+/p shallow junctions (< 0.15 um) with reverse current density of few nA/cm2 and low contact resistivity (∼ 5×10–7 Ω cm2) have been fabricated by using Mo suicide and Rapid Thermal Annealing (RTA). The processes of implantation through Mo films and into MoSi2 layers have been comparatively analysed on the basis of SIMS and carrier concentration profiles, TEM observations and DLTS measurements. In the case of n+/p diodes fabricated by ITM technology slightly worse leakage currents have been observed, in spite of the better planarity of the silicide-silicon interface exhibited by these structures.
Change in Magnetic Characteristic Of Stainless-Steel by Laser and Ion Beams
Authors: Sanda Hiroyuki , Takai Mikio , Namba Susumu , Chayahara Akiyoshi , Satou Mamoru 
Published: March 2011

ABSTRACTFocused Ar-ion laser and MeV ion beams were impinged onto stainless-steel foils to investigate the localized modification of the magnetic property associated with the phase transformation. The magnetic signal intensity of the Ar-ion laser irradiated areas was found to locally decrease at a laser power of 350 mW and almost extinguish at 550 mW with a beam spot size of 13.2 μm (at 1/e intensity) because of the localized retransformation into austenite. On the other hand, the magnetic signal intensity was found to increase by 3 MeV Au+ implantation because of the localized martensitic transformation. The magnetic signal for ferromagnetic substrates was much more enhanced than that for non-magnetic substrates. These results indicate that the beam-induced localized phase-transformation in stainless-steel can be applied to fixed magnetic recording.
Metastable Structures in Quenched Cr-Ti and Electron Irradiated Cu-Ti Alloys
Authors: Sinkler W. , Luzzi D.E. 
Published: March 2011

ABSTRACTElectron diffraction and imaging are used to characterize and contrast the structures and microstructures of a metastable Cr-Ti phase formed after quenching and a metastable Cu-Ti phase formed during electron irradiation. In both phases, marked structural anisotropies are found which have characteristics common to both of these bcc-based materials. It has been reported in the literature that this quenched-in metastable Cr-Ti phase undergoes a spontaneous structural relaxation into the amorphous state during sub-eutectoid temperature anneals [1]. Despite the similarity of the present experiments to those reported in the literature, an amorphization transformation was not observed. It is argued that the amorphization of this material requires the stabilization of the amorphous phase by an impurity.
Ion Beam Method to Study Fractal Aggregation of Magnetic Particles on Thin Solid Films:
Authors: Ding J.R. , Huang L. , Liu B.X. 
Published: March 2011

ABSTRACTThis paper presents the experimental observations of Fractal Aggregates on thin solid films after either directly thin film deposition or additional ion irradiation. A linear correlation was found between the fractal dimension and the atomic magneton of the aggregating particles of Fe, Co, Cr and Ni.
Adhesion of Silver Films to Ion-Bombarded Alumina
Authors: Erck R. A. , Fenske F. R. 
Published: March 2011

ABSTRACTSilver films were deposited on alumina substrates using ion bombardment. Adhesion strength was measured as a function of deposition conditions, sputter-cleaning time, and bombarding ion species, using a pull-type adhesion tester. Argon- and argon/oxygen-ion sputtering produced large increases in adhesion strength, with the greatest increases occurring for oxygen-ion bombardment. Adhesion strength increased monotonically as a function of ion sputtering time. At a given deposition rate, further enhancement of adhesion is seen with concurrent ion bombardment.
Irradiation-Induced Grain Growth: Role of Dislocations
Authors: Allen Charles W. , Rehn Lynn E. 
Published: March 2011

ABSTRACTExisting theories of irradiation-induced grain growth assume that growth occurs by the boundary migration mechanism commonly observed for thermal growth and that it is only the point defects generated si boundaries during the irradiation which are responsible for boundary migration. In contrast, in situ observations during ion irradiation of Au films at temperatures less than 20 K even have clearly demonstrated that growth occurs both by boundary migration and by grain coalescence. Here we present further evidence for the latter. Furthermore, the substantial defect cluster activity observed during irradiation suggests that dislocations play a significant role in the growth phenomenon. Here, we also demonstrate qualitatively that glide of such dislocations to or “through” a boundary can produce essentially the same effect on boundary position or structure that the original point defects would have had if they had migrated individually to or through the boundary. Via dislocation motion, point defects originating far from a boundary may induce boundary migration or boundary structure change, and hence, grain growth.
Uv Excimer Laser-Induced Deposition of Palladium from Palladium Acetate Films
Authors: Esrom Hilmar , Wahl Georg 
Published: March 2011

ABSTRACTUV excimer laser-induced deposition of palladium from spin coated palladium acetate films in air is described. We have investigated mainly the deposition of palladium on aluminum oxide and quartz substrates and its dependence on the fluence and the number of excimer laser pulses. The decomposition mechanism was studied by measuring in situ the transmitted pulse energy during the exposure process. We have found that the excimer laser-induced decomposition of palladium acetate films is mainly pyrolytic and a simple model can be used to describe the decomposition process.
In Situ Characterization of Metallorganic Chemical Vapor Deposition
Authors: Scarmozzino R. , Cacouris T. , Osgood R.M. 
Published: March 2011

ABSTRACTIn situ measurement of resistance has been used for the realtime monitoring of metallorganic chemical vapor deposition (CVD) growth characteristics. In particular, a novel technique for measuring metallorganic CVD activation energies is presented. The micron scale geometry of the experiment makes it relevant to work in localized laser CVD. The technique has been used to measure the CVD activation energy of dimethylaluminum hydride (DMAlH). In addition, a variant of the technique has been used to study the growth stage of a resistless two-step metallization process (nucleation / selective CVD) employing DMAIH as the source gas in both steps.
Wavelength-Dependent Area Selectivity in Photochemical Vapor Deposition of Aluminum Films
Authors: Hanabusa Mitsugu , Ikeda Masashi 
Published: March 2011

ABSTRACTThickness profile of aluminum thin films deposited from dimethylaluminum hydride on silicon substrate changed with wavelengths of light chosen from the wide emission spectra of a deuterium lamp. Under illumination of the VUV around 160 nm deposits were formed preferentially in illuminated regions, while such area selectivity was lost and uniformly thick films were deposited all over the substrate when the UV around 240 nm was used. The observed area selectivity can be interpreted as arising from a wavelength-dependent nucleation mechanism; namely, surface photochemical reactions leading to nucleation are induced only by the VUV, while the UV photons are capable of producing photofragments in gas phase responsible for nucleation.
Selective Rapid Thermal Cvd of Germanium
Authors: Grider D.T. , Özttürk M.C. , Wortman J.J. , Littlejohn M.A. , Zhong Y. , Batchelor D. , Russell P. 
Published: March 2011

ABSTRACTSelective depositions of germanium thin films have been investigated in a cold-wall, lamp heated rapid thermal processor. Films were deposited at low pressures (1 Torr-8 Torr) using the thermal decomposition of germane. Selectivity was maintained throughout the temperature range investigated, 350°C-600°C. Growth rates as high as 800 Å/min were obtained at 425°C where deposition is controlled by the surface reactions, making germanium compatible with the throughput requirements of single wafer manufacturing. Three dimensional growth was seen at temperatures above 450°C resulting in a rough surface morphology. Smooth films were deposited below 450°C with the films characterized by two dimensional growth. In this work, germanium is considered as a potential material to fabricate MOS transistors with raised source and drain junctions (UPMOS). Kelvin structures were fabricated to study the effect of the intermediate germanium layer between aluminum and silicon on contact resistance. It is shown that contact resistivity is improved by approximately 17% using an Al/p-Ge/p+-Si structure. In this work, it is also shown that titanium germanide formation can be used as a means of reducing the resistivity of the Ge buffer layer.
Direct Writing of Copper Lines from Copper Formate Precursors Using a Nd:Yag-Laser
Authors: MOLLER Heinrich G. , Schuler Siegfried 
Published: March 2011

ABSTRACTAn effective method is described for laser induced additive formation of copper conductor lines on alumina substrates. The direct writing process allows for depositions with speeds of up to 50 mm/s and a resolution of about 10 microns with reliable adhesion of the deposited patterns.
Surface Chemistry of Dimethylaluminum Hydride and Trimethylaluminum on Aluminum
Authors: Strongin Daniel R. , Comita Paul B. 
Published: March 2011

ABSTRACTThe surface chemistry of dimethylaluminum hydride (DMAH) and trimethylaluminum (TMA) on aluminum has been investigated with temperature programmed desorption (TPD), and Auger electron spectroscopy (AES). The TPD spectra of TMA shows a single desorption peak with a peak maximum which shifts from 190 to 200 K for surface coverages of 0.5 and 2.0 monolayers (ML) respectively. DMAH desorbs from an aluminum surface between 198 and 236 K at surface coverages ranging from 0.1 to 4.0 ML. A second DMAH desorption peak is observed at about 200 K (2.0 ML) when the aluminum surface is contaminated with carbonaceous species, resulting from the decomposition of DMAH. Both DMAH and TMA yield methane as a reaction product on the aluminum surface. The surface reactions of DMAH on aluminum also yield TMA as a reaction product.
In Situ Measurement of Pulsed Laser Indxuce Carrier Ceneraticn in Doped Silicon Films
Authors: Saveshimn T. , Hara M. , Usui S. 
Published: March 2011

ABSTRACTTransient conductance measurements were used to study rapid carrier generation during the laser doping of a silicon film. The movement of the liquid-solid interface was measured and the point of initiation of carrier generation frcn dopant atoms diffused to the molten silicon was determined. It was established that the dopant atais are activated at the nmorent the dopant diffused region solidified. Also, the laser doping technique was used to fabricate polycrystalline silicsn thin film transistors (Poly-Si TFT's) ata processing temperature of 250ºC.
Substrate Heating Effects in Excimer Laser Planarization of Aluminum
Authors: Baseman Robert J. , Andreshak Joseph C. 
Published: March 2011

ABSTRACTSubstantial improvements in excimer laser planarization processes are observed with substrate heating. Cavities, associated with filling of high aspect ratio vias at low substrate temperature, can be eliminated by substrate heating. Damage associated with pulse overlap regions can be temperature sensitive, and is reduced as substrate temperatures areincreased. While required fluences for planarization and sample damage both decrease as the sample temperature increases, the relative insensitivity of the damage threshold generally results in larger process windows at higher temperatures. We also report model calculations of the effect of substrate heating on sample temperature distributions and the durations of the laser driven melts.
Phosphorus Doping into Silicon Using ArF Excimer Laser
Authors: Slaoui Abdelilah , Foulon Francois , Fogarassy Eric , Siffert Paul 
Published: March 2011

ABSTRACTChemical doping of single-crystal silicon in a PF5 atmosphere is performed byirradiation with an ArF excimer laser working at 193 nm. We have investigated the dependence of doping parameters such as the number of pulses and PF5 gas pressure on the sheet resistance and the impurity concentration profiles. From these results, it is found that phosphorus atoms are produced by pyrolysis of PF5 molecules adsorbed (chemisorbed at low pressure and physisorbed at pressure higher than 1 Torr) on thesilicon surface. As for the incorporation mechanism, it is shown that the process is external rate limited for doping in PF5 ambient whereas mainly diffusion limitedfor doping using only the chemisorbed layer.