bluuebunny/crossref_metadata_2025_split huggingface dataset:
From Pong to Pokemon Go, catching the essence of the Internet Gaming Disorder diagnosis
Authors: Carbonell Xavier 
Published: March 2017

Taking as a starting point, this commentary proposes some issues regarding the diagnosis of Internet Gaming Disorder discussed in Kuss et al. (2016). In our opinion, the confusion in DSM-5 diagnosis could be due to the weak starting point in building the criteria. The criteria such as functional impairment and stability of the dysfunctional behavior are considered. It is suggested that avatar identification, playing motivations, and types of video games should be considered for diagnosis. The diagnostic process is highly influenced by social context and the rapid development of video game industry. The commentary ends by considering the distinction between online and offline video gaming and the critical consideration of everyday behaviors as being addictive.
Energetics of Interstitial Hydrogen and Hydrogen Diffusion in Realistic Models of a-Si:H
Authors: Fedders P. A. 
Published: March 2017

AbstractIn order to determine the mechanism or mechanisms of hydrogen transport in a-Si:H one must identify the reactions that bring deeply bonded H (on dangling bonds) to the transport band which is some form of interstitial hydrogen. Further, one must have reliable estimates of the energy difference between these deep states and transport states as well as the barrier energies among transport sites. In this paper we consider all of these ingredients in order to partially explain how hydrogen migrates in a-Si:H.
High Hydrogen Content Silicon Nitride For Photovoltaic Applications Deposited By Hot-Wire Chemical Vapor Deposition
Authors: Holt Jason K. , Swiatek Maribeth , Goodwin David G. , Atwater Harry A. , Watson Thomas J. 
Published: March 2017

AbstractSilicon nitride films have been grown by hot-wire chemical vapor deposition and film properties have been characterized as a function of SiH4/NH3 flow ratio. Quadrupole mass spectrometry measurements revealed that NH3 should be present in large excess relative to SiH4 (<10), due to its lower decomposition probability on the wire. Silicon nitride films were produced with refractive indices ranging from 1.8-2.5 and H-content from 9-18 atomic % as the flow ratio increased from 1% to 8%. Fourier Transform Infrared Spectroscopy revealed a change from predominantly N-H to Si-H bonding as the flow ratio increases beyond 6%. Subsequent annealing studies showed different kinetics for H release from Si versus N. Films grown with a low SiH4/NH3 ratio were found to oxidize readily (23 atomic %), while larger ratios yielded no oxygen incorporation.
H NMR Evidence for a Change in The Local Hydrogen Environment of Sites Associated with the Staebler-Wronski Effect in a-Si:H
Authors: Su T. , Plachy Robin , Taylor P. C. , Stone S. , Ganguly G. , Carlson D. E. 
Published: March 2017

AbstractWe study the H NMR line shapes of a sample of a-Si:H under several conditions: 1) as grown, 2) light-soaked for 600 hours, and 3) light-soaked followed by annealing at different temperatures. At T = 7 K, the NMR line shape of the sample after light soaking exhibits an additional doublet compared to that of the sample as-grown. This doublet is an indication of a closely separated hydrogen pair. The distance between the two hydrogen atoms is estimated to be about (2.3 ± 0.2) Å. The concentration of these hydrogen sites is estimated to be between 1017 and 1018 cm-3 consistent with ESR measurements of the defect density after light soaking. This doublet disappears after the sample is annealed at 200°C for 4 hours.
Thin Film Microelectromechanical Systems
Authors: Chu V. , Gaspar J. , Conde J.P. 
Published: March 2017

AbstractThis paper presents the fabrication and characterization of MEMS structures on glass substrates using thin film silicon technology and surface micromachining. The technology developed to process bridge and cantilever structures as well as the electromechanical characterization of these structures is discussed. This technology can enable the expansion of MEMS to applications requiring large area and/or flexible substrates. The main results for the characterization of the movement of the structures are as follows: (1) in the quasi-DC regime and at low applied voltages, the response is linear with the applied dc voltage. Using an electromechanical model which takes into account the constituent materials and geometry of the bilayer, it is possible to extract the deflection of the structures. This estimate suggests that it is possible to control the actuation of these structures to deflections on the sub-nanometric scale; (2) resonance frequencies of up to 20 MHz have been measured on hydrogenated amorphous silicon (a-Si:H) bridge structures with quality factors (Q) of 70-100 in air. The frequency depends inversely on the square of the structure length, as predicted by the mechanical model; and (3) using an integrated permanent magnet/magnetic sensor system, it is possible to measure the structure movement on-chip and to obtain an absolute calibration of the deflection of the structures.
Carrier Generation in Thin-Film Polysilicon
Authors: Eccleston W. 
Published: March 2017

AbstractThere is a need to understand carrier generation polysilicon TFTs. When the generation is stimulated by the depletion of the material, due to the field effect, carriers are drawn to the surface and move along it by a process akin to diffusion. At some gate voltage the supply of carriers to the channel is insufficient to maintain the current flow. This leads to a reverse bias across the drain junction. It is proposed that carrier generation that occurs mainly near to the drain is more likely to be stimulated by increases of drain rather than gate voltage. The temperature dependence of currents at the current minimum, and at current saturation, of the transfer characteristic are described and are used to justify the model for generation and flow.
Experimental investigation and modelling of light scattering in a-Si:H solar cells deposited on glass/ZnO:Al substrates
Authors: Krc J. , Zeman M. , Kluth O. , Smole F. , Topic M. 
Published: March 2017

AbstractThe descriptive scattering parameters, haze and angular distribution functions of textured ZnO:Al transparent conductive oxides with different surface roughness are measured. An approach to determine the scattering parameters of all internal interfaces in p-i-n a-Si:H solar cells deposited on the glass/ZnO:Al substrates is presented. Using the determined scattering parameters as the input parameters of the optical model, a good agreement between the measured and simulated quantum efficiencies of the p-i-n a-Si:H solar cells with different interface roughness is achieved.
Light-intensity and temperature dependence of trap-dangling bond recombination in hydrogenated microcrystalline silicon
Authors: Boehme Christoph , Lips Klaus 
Published: March 2017

AbstractA quantitative study of the trap-dangling bond tunneling recombination in hydrogenated microcrystalline silicon (μc-Si:H) is presented. The transition coefficients were measured at various light exposures and temperatures between T = 10 K and T = 140 K using time-domain measurements of spin-dependent recombination (TSR). TSR is a new characterization method related to electrically detected magnetic resonance (EDMR). It combines the advantages of pulsed electron spin resonance with that of EDMR. In contrast to previous models, the experimental results can only be interpreted if the interaction between the spins of the trap and the dangling bonds as well as triplet recombination is considered.
Real Time Spectroscopic Ellipsometry of Amorphous Silicon Grown at High Deposition Rates by Hot-Wire CVD
Authors: Nelson Brent P. , Levi Dean H. 
Published: March 2017

AbstractWe use real-time spectroscopic ellipsometry (RTSE) for in-situ characterization of the optical properties and surface roughness (Rs) of hydrogenated amorphous silicon (a-Si:H) grown by hot-wire chemical vapor deposition (HWCVD) with varying deposition rates (5 to 120 Å/s). Early time evolution of the Rs during growth is remarkably similar for all deposition rates. During the first few Ås of growth, there is a sharp increase in Rs as the a-Si:H nucleates in separate islands. This is followed by a reduction of Rs as these areas coalesce into a bulk film, which occurs at an average thickness of 100 Å. After coalescence the Rs rises to a stable value that is dependent upon growth conditions with a general tendency for the Rs to increase with growth rate. However, neither the Rs nor the material electronic properties are unique for a given deposition rate. Films grown under high silane flow and low pressure have a better photoresponse and a lower Rs than films grown at the same deposition rate but with low silane flow and high pressure. We observe a stronger correlation of film properties with Rs than with deposition rate; namely a monotonic decrease in photo-response, and increase in optical gap, with increasing Rs.
Recent Progress in Industrial Applications of CAT-CVD (Hot-Wire Cvd)
Authors: Masuda Atsushi , Izumi Akira , Umemoto Hironobu , Matsumura Hideki 
Published: March 2017

AbstractRapid progresses are achieved in catalytic CVD (Cat-CVD), often called hot-wire CVD, in the past 3-years NEDO national project in Japan. Cat-CVD technology presents many advantages in thin-film formation processes; high-efficiency of gas use, large-area deposition, no ion bombardment and low-temperature deposition even below 200°C. All of the elemental techniques for the industrially applicable Cat-CVD apparatuses, such as the suppression of the metal contamination, the precise control of the substrate temperature, the life extension of the catalyzer, 1-m size uniform deposition and the chamber cleaning, have been completely developed. Sophisticatedly designed substrate holder with electrostatic chuck and showerhead equipped with catalyzers are both key technologies for these achievements. High reproducibility for film properties is also obtained by controlling the reaction between high-density radicals and chamber walls. Prototype mass-production apparatus for SiNx passivation films in GaAs devices has been already developed and this will be probably the first application of Cat-CVD in industry. These recent movements appear to promise the drastic revolution in semiconductor and flat-panel display industries by introducing Cat-CVD in very near future.
Amorphous Silicon Films and Superlattices Grown by Molecular Beam Epitaxy: An Optical Analysis
Authors: Lockwood D. J. , Baribeau J.-M. , Noël M. , Zwinkels J. C. , Fogal B. J. , Orapunt F. , O'leary S. K. 
Published: March 2017

AbstractWe produce a novel form of amorphous silicon through ultra-high-vacuum molecular beam epitaxy. By depositing silicon atoms onto a fused quartz substrate at temperatures between 98 and 335°C, we obtain a silicon-based material that lacks the characteristic periodicity of crystalline silicon but nevertheless has 98% of its density. The impurity content of this material is studied through infrared and secondary ion mass spectroscopies. The primary impurity found is oxygen, with hydrogen and carbon atoms also being found at trace levels. The Raman spectra of the amorphous silicon films are measured and the results, as they relate to the presence of disorder, are interpreted. We also use this molecular beam epitaxy method to fabricate a number of amorphous silicon superlattices, comprised of thin layers of amorphous silicon separated with even thinner layers of SiO2. The optical properties of the films and superlattices are contrasted.
Microwave PECVD of Micro-Crystalline Silicon
Authors: Soppe Wim , Devilee Camile , Schiermeier Sacha , Donker Harry , Rath J.K. 
Published: March 2017

AbstractThe deposition of micro-crystalline silicon by means of PECVD with a new linear microwave plasma source is investigated. This plasma source has successfully been introduced in the large scale production of multi-crystalline Si solar cells for the deposition of passivating silicon nitride layers. Advantages of this linear plasma source are the high deposition rates and the large area (up to 80 cm width, no length limitations) on which a homogeneous deposition can be achieved. Since this source has not been applied for deposition of micro-crystalline silicon before, we explored a large parameter space (substrate temperature, pressure, MW-power, gas flow rates), in order to find optimum growth conditions. It is observed that with this microwave source it is possible to grow micro-crystalline layers at significantly higher silane/hydrogen ratios and higher deposition rates than for conventional RF PECVD. In this paper, structural properties of the silicon layers, as investigated by Raman and FTIR spectroscopy, XRD and SEM measurements are discussed.
Ultrafast Carrier Thermalization in Hydrogenated Amorphous Silicon
Authors: Dexheimer S. L. , Zhang C. P. , Liu J. , Young J. E. , Nelson B. P. 
Published: March 2017

AbstractWe present detailed studies of the initial relaxation processes of photoexcited carriers in hydrogenated amorphous silicon. We have carried out time-resolved measurements of the photoexcited carrier response in HWCVD a-Si:H thin films using a wavelength-resolved femtosecond pump-probe technique, in which an intense 35-fs pump pulse excites carriers in the sample and a time-delayed probe pulse measures the resulting change in optical properties as a function of time delay following the pump pulse. Measurements of the transient optical absorbance were carried out as a function of the density of excited carriers, sample temperature, and probe wavelength. These studies indicate fast carrier thermalization via phonon emission on a ∼ 150 fs time scale and rapid phonon equilibration on a ∼ 230 fs time scale.
Recombination of Optically Excited Carriers in a-Si:H at Low temperatures and Intermediate Times
Authors: Whitaker J. , Su T. , Taylor P. C. 
Published: March 2017

AbstractOptically induced electron spin resonance (LESR) studies on time scales in between the previously published PL and LESR results (approximately 10 ms to 10 s) allow one to examine the cross over between energy-loss (downward) hopping of carriers and carrier recombination via tunneling. In addition, data in this time regime are directly compared in the same sample with NMR data on the dipolar spin-lattice relaxation of the bonded hydrogen where light induced electrons and holes are responsible for dipolar relaxation of bonded hydrogen. The LESR results confirm the interpretation of the NMR measurements.
Structural and Electrical Characterization of B-Doped Microcrystalline Silicon thin Films
Authors: Saleh R. , Nickel N. H. 
Published: March 2017

AbstractIn this paper we present the results for boron-doped microcrystalline silicon deposited at low temperature (230°C) by PECVD method. The structural and electrical properties are investigated as a function of boron concentrations using Raman, dark conductivity, hydrogen effusion and Hall effect measurements. The results show that the incorporation of boron induced an amorphization in the μc-Si:H films structure. A structural change due to boron incorporation is also accompanied by a change in hydrogen bonding environment. High conductive film of our boron-doped μc-Si:H films is attained at boron concentration 2000 ppm which consists nearly the same fraction of crystalline and amorphous phase (XC ~55 %).
Study of Amorphous to Microcrystalline Silicon Transition from Argon Diluted Silane
Authors: Gupta N. Dutta , Ray P. P. , Chaudhuri P. , Das U. K. , Vignoli S. , Jardin C. 
Published: March 2017

AbstractWe have studied the structural evolution in amorphous and microcrystalline silicon deposited from silane-argon mixture by radio frequency plasma enhanced chemical vapour deposition (PECVD) method. Sharp increase in small angle x-ray scattering (SAXS) intensity, in accordance with tilt measurements, indicates columnar morphology in the sample deposited in the amorphous-microcrystalline transition region. The variation of SAXS measured heterogeneity and a gradual shift of Si-H stretching vibrational frequency at 2000 cm-1 towards higher wave number with increase of power density indicate structural modifications in the films. Observation of sharp increase in the ratio of the intensity of Ar* to SiH* in the transition region may explain the surface modification assisted by Ar* and hence the structural changes in the material.
Electron Spin Resonance and Electronic Conductivity in Moderately Doped n-type Microcrystalline Silicon as a Probe for the Density of Gap States
Authors: Dylla T. , Carius R. , Finger F. 
Published: March 2017

AbstractElectron spin resonance accompanied by conductivity measurements in n-type microcrystalline silicon with different doping concentrations and different structure compositions has been applied for the study of the density of gap states and the influence of these states on charge carrier density. We studied doping concentrations close to the defect density where the doping induced Fermi level (EF) shift is determined by compensation of gap states. We found a correlation between the EF shift, the intrinsic defect density and structural changes.
Metal-Free Germanium-Induced Crystallization of Amorphous-Si on Glass
Authors: Akhavan A. , Rezaee L. , Derakhshandeh J. , Mohajerzadeh S. , Goodarzi A. 
Published: March 2017

AbstractA metal-free germanium-induced crystallization technique is reported to realize poly-silicon films on glass at temperatures as low as 480°C. The reduction in crystallization temperature is achieved by using ultra-violet illumination during thermal treatment of the amorphous silicon layer. The annealed samples have been studied using SEM and XRD analyses. Also the electrical conductivity of samples with various annealing conditions has been examined. Conductivity of the samples annealed in the presence of ultra-violet exposure shows more than three orders of magnitude improvement compared to that of amorphous films. Samples treated without UV exposure do not show much enhancement. Size of poly-silicon grains is 0.3μm, as revealed using SEM study.
Proton NMR Hole-Burning in Hot Wire a-Si:H
Authors: Herberg J. , Fedders P. A. , Leopold D. J. , Norberg R. E. , Schropp R. E. I. 
Published: March 2017

AbstractProton NMR near 200 MHz has been used to examine the dynamics of hole-burning in HWCVD a-Si:H films deposited from SiH4. Radiofrequency hole-burning is a tool to distinguish inhomogeneous broadening from homogeneous broadening. The 3 kHz FWHM resonance line from T-site-trapped H2 molecules shows a hole-burn behavior similar to that found for PECVD a-Si:H films, as does the 24 kHz FWHM line from clustered silicon-bonded hydrogens. However the ∼80 kHz FWHM superbroad line varies with tip angle uniformly across the line for hole-burns applied at any location within ∼50 kHz from the resonance center. The superbroad line is homogeneously broadened and apparently arises from superclose SiH clusters with inter-proton distances considerably less than 2 Å.
Correlation of Light-induced Enhancement of Open-Circuit Voltage and Structural Change of Heterogeneous Silicon Solar Cells
Authors: Yang Jeffrey , Lord Kenneth , Yan Baojie , Banerjee Arindam , Guha Subhendu , Han Daxing , Wang Keda 
Published: March 2017

AbstractWe observe a significant light-induced increase in the open-circuit voltage, Voc, of thin-film silicon solar cells whose intrinsic (i) layer consists of an amorphous and microcrystalline mixed phase. The increase depends on the i-layer thickness, the i-layer deposition temperature, the initial Voc values, and the light-soaking intensity. An increase of as large as 150 mV is observed. The original Voc is restored after subsequent thermal annealing. In-situ photoluminescence (PL) spectroscopy is used to investigate this metastable phenomenon. We find that the PL intensity and peak-energy position associated with the amorphous component of the heterogeneous material increase upon light soaking, suggesting a structural change. We propose that a reduction of microcrystalline volume fraction or size is responsible for the Voc enhancement.
Hydrogenated Microcrystalline Silicon Solar Cells Made with Modified Very-High-Frequency Glow Discharge
Authors: Yan Baojie , Lord Kenneth , Yang Jeffrey , Guha Subhendu , Smeets Jozef , Jacquet Jean-Marie 
Published: March 2017

AbstractHydrogenated microcrystalline silicon (μc-Si:H) solar cells are made using modified veryhigh-frequency (MVHF) glow discharge at deposition rates ∼3-5 Å/s. We find that the solar cells made under certain conditions show degradation in air without intentional light soaking. The short-circuit current drops significantly within a few days after deposition, and then stabilizes. We believe that post-deposition oxygen diffusion along the grain boundaries or cracks is the origin of the ambient degradation. By optimizing the deposition conditions, we have found a plasma regime in which the μc-Si:H solar cells do not show such ambient degradation. The best a-Si:H/μc-Si:H double-junction solar cell has an initial active-area efficiency of 10.9% and is stable against the ambient degradation. The stability data of the solar cells after light soaking are also presented.
A Study of Fabrication and Characterization of Ultra-Small Polycrystalline Silicon Islands for Advanced Display and Microsensor Applications
Authors: Schmidt Dominik , Shi Frank , Pianetta Piero 
Published: March 2017

AbstractPolycrystalline silicon (polysilicon) is a key component of integrated circuit technology, micromechanical systems and displays. High-mobility polysilicon thin-film transistors are replacing amorphous-silicon transistors in advanced active-matrix displays, and are also vital to the emerging fields of microsensors and microactuators [1]. In this study, the deposition processes (LPCVD) of polysilicon thin films were carefully studied and the basic kinetics were analyzed. The films were patterned into submicron islands and the relation of the deposition temperature versus the crystallinity of polysilicon islands was observed. A “threshold” deposition temperature for polysilicon crystals larger than 0.35 μm was found. The relationships of polysilicon crystal sizes vs. annealing temperature and vs. annealing duration were also systematically studied. Polysilicon islands of ∼ 0.1 μm lateral dimensions were successfully fabricated by ebeam lithography and several types of annealings were performed to increase micro-crystal size, with the goal of creating single-crystal high-mobility islands. Theoretically, transistors built from such islands should match the performance of state-of-the-art bulk CMOS devices. The crystal size was measured using TEM and AFM analysis. Moreover, EXAFS (Extended X-ray Absorption Fine Structure) measurements at SSRL (Stanford Synchrotron Radiation Lab) were employed to study the crystallization processes of polysilicon films and the correlation between the absorption curves, the thin-film electrical properties and the polysilicon grain sizes.
Infrared Charge-Modulation Spectroscopy of Defects in Phosphorus Doped Amorphous Silicon
Authors: Zhu Kai , Schiff E. A. , Ganguly G. 
Published: March 2017

AbstractWe present infrared charge-modulation absorption spectra on phosphorus-doped amorphous silicon (a-Si:H:P) with doping levels between 0.17%-5%. At higher doping levels (1% - 5%) we find a sharp spectral line near 0.75 eV with a width of 0.1 eV. We attribute this line to the internal optical transitions of a complex incorporating four fold coordinated phosphorus and a dangling bond. This line is barely detectable in samples with lower doping levels (below 1%). In these samples a much broader line dominates the spectrum that we attribute to uncomplexed dopants. The relative strength of the two spectral features is in rough agreement with a model proposed by Street that has not been previously tested experimentally.