bluuebunny/crossref_metadata_2025_split huggingface dataset:
Garnet layers prepared by liquid phase epitaxy for microwave and magneto‐optical applications – a review
Authors: Aichele T. , Lorenz A. , Hergt R. , Görnert P. 
Published: July 2003

AbstractThe magnetic iron garnets possess two outstanding properties, an excellently narrow linewidth of the ferromagnetic resonance and a magneto‐optical activity that is without competition when the iron garnet is substituted with bismuth. Here the growth of bismuth substituted iron garnet layers with a bismuth content of up to 1.8 formula units is reported. The influence of solution compositions and undercooling on the growth and bismuth incorporation is discussed. Morphological instabilities due to misfit stress are avoided by the use of lattice‐matched substrates. Two applications of iron garnet layers, namely a electronically controllable magnetostatic delay line for the communication technology in the GHz range and magneto‐optic garnet sensor layers for real‐time visualisation of eddy currents with high spatial resolution for the non‐destructive evaluation are presented. Furthermore the detection, measurement, and visualisation of magnetic fields by magneto‐optic garnet layers are reviewed.
Growth of high resistivity CdTe and (Cd,Zn)Te crystals
Authors: Fiederle M. , Babentsov V. , Franc J. , Fauler A. , Konrath J.‐P. 
Published: July 2003

AbstractThe growth of high resistivity CdTe and (Cd,Zn)Te is successfully performed with different kinds of doping. In the literature intentionally undoped as well as doped crystals are presented with resistivities up to 1010 Ωcm. In this paper we review the growth of high resistivity CdTe and (Cd,Zn)Te. The mechanism of compensation is discussed regarding the different dopants and deep levels, which seem to be responsible for the high resistivity. A common compensation model explains the high resistivity by deep levels. The doping and the influence on the compensation mechanism is compared for several elements like tin, germanium and chlorine. The material properties and the crystal quality of undoped and doped CdTe as well as (Cd,Zn)Te are shown.
Solid–vapor equilibrium in quasi‐binary CdTe—ZnTe
Authors: Greenberg J. H. , Guskov V. N. , Alikhanyan A. S. 
Published: July 2003

AbstractTotal vapor pressure measurement and Knudsen cell mass spectrometry have been applied to study sublimation processes in the quasi‐binary system CdTe—ZnTe at temperatures 780 K – 1350 K. This system was shown to correspond to the vapor pressure minimum in the pressure–temperature–composition (P–T–X) phase diagram of the ternary system Cd—Zn—Te. The shape of the solidus and vaporus surfaces was traced via experimental isothermal and isobaric sections of the Pmin area up to the near‐melting region. Relationship between the composition of the crystal, vapor pressure and composition of the vapor was determined in the whole concentration range. At temperatures above 780 K CdTe—ZnTe was found to be a continuous solid solution with incongruent sublimation, whereas at T = 780 K a tendency to phase separation was observed.
Macrosegregation in the growth of doped III‐V‐semiconductors from the solution
Authors: Danilewsky A. N. , Meinhardt J. 
Published: July 2003

AbstractIn case of the solution growth of S‐doped InP bulk crystals from the In solution the solutal convection plays the dominant role for the transport of matter even under microgravity conditions. A measure for the strength of convection is the macrosegregation. For various boundary conditions the axial segregation is described with modified classical segregation models. The measured and calculated physical parameters such as effective distribution and diffusion coefficients respectively allow a consistent formulation of macro‐ and microsegragtion.
Beam induced lateral epitaxy: a new approach for lateral growth in molecular beam epitaxy
Authors: Suzuki T. , Naritsuka S. , Maruyama T. , Nishinaga T. 
Published: July 2003

AbstractEpitaxial lateral growth has been conducted without using oxide masks by a new technique called as beam induced lateral epitaxy (BILE). In this technique, molecular beams are sent in a glancing angle with respect to a substrate in MBE and a large lateral growth was accomplished on a side of pre‐fabricated truncated ridges on the substrate. By using BILE we have successfully grown GaAs in lateral direction on GaAs(001) substrate. It was found that the growth behavior of BILE depends strongly on incident angle of the Ga beam. With the incident angle of 12°, a lateral growth of nearly 6μm wide was achieved.
Effect of oxygen partial pressure on silicon single crystal growth by floating zone technique: surface oxidation and Marangoni flow
Authors: Hibiya Taketoshi , Asai Yoshihiko , Sumiji Masanobu , Kojima Toshiya 
Published: July 2003

AbstractSilicon single crystals were grown by the floating‐zone method using an infrared image furnace in the wide range of oxygen partial pressure defined at the inlet of the furnace from 1×10−2Pa to 8.2×102Pa (Po2surface= 5.3 × 10−24Pa to 3.6 × 10−14Pa), so that the Marangoni number was changed from 2070 to 616. Degree of surface oxidation of the grown crystal was dependent on oxygen partial pressure of an ambient atmosphere. Striation pattern in almost all crystal shows a single frequency. AtPo2inlet= 4.9 × 102Pa (Po2surface= 1.3 × 10−14Pa: imaginary Marangoni number of 700) precipitation of SiO2was observed at the melt surface. AtPo2inlet= 8.2 × 102Pa (Po2surface= 3.6 × 10−14Pa: imaginary Marangoni number of 616), which is over the equilibrium oxygen partial pressure for a SiO2phase, the silicon specimen was polycrystallized and showed no growth striation. Temperature coefficient of surface tension |‐∂σ/∂T| less than 0.25 × 10−3N/m‐K is not realistic, although many small values have been reported.
Influence of liquid bridge volume on the floating zone convection
Authors: Hu W. R. , Tang Z. M. 
Published: July 2003

AbstractThe liquid bridge volume is a critical geometrical parameter in addition to the aspect ratio for onset of oscillation in the floating zone convection. The oscillatory features are generally divided into two characteristic regions: slender liquid bridge region and fat liquid bridge region. The oscillatory modes in two regions are discussed in the present paper.
Influence of high frequency vibrations on fluid flow and heat transfer in a floating zone
Authors: Lyubimova T. P. , Scuridin R. V. , Cröll A. , Dold P. 
Published: July 2003

AbstractThis paper deals with the numerical simulation of fluid flow and heat transfer in a silicon floating zone (FZ) subjected to axial vibrations. Corresponding experiments were performed under microgravity conditions within the framework of the European sounding rocket Maxus‐4 flight. The study concerns a liquid zone maintained between two rigid rods of equal radii. The growing crystal is subjected to vibrations in the direction of the zone axis. Numerical modelling of the convective heat transfer in the liquid zone is carried out accounting for melting and crystallization. The flows and the heat transfer in the melt are calculated on the basis of the equations of thermal vibrational convection under non‐uniform vibrations. The calculations are made for zero gravity and 1‐g conditions accounting for both pulsational and average deformations of the free surface. The temperature at the free surface is fixed and corresponds to the experimental one. The shape and the position of the solid‐liquid interfaces are given by the isotherm of the melting point of the material. The problem is solved by a finite difference method. The boundary‐fitted curvilinear coordinate system is employed. The calculations are made for the parameters corresponding to the radiation heated floating zone growth of silicon, i.e. a crystal diameter of 10 mm and an aspect ratio of the melt zone between 1 and 1.5. The vibration amplitude is varied in the range of 3 to 4.5 μm and the vibration frequency lays in the interval of 2 to 4.5 kHz. It is shown that for zero gravity and for 1‐g conditions, the vibrations lead to a decrease of the thermocapillary flow intensity near the crystal‐melt interface. For zero gravity conditions vibrations lead to a flattening of the crystallization front.
29Si and 30Si single crystal growth by mini‐Czochralski technique
Authors: Abrosimov N. V. , Riemann H. , Schröder W. , Pohl H.‐J. , Kaliteevski A. K. , Godisov O. N. , Korolyov V. A. , Zhilnikov A. Ju. 
Published: July 2003

Abstract29Si and 30Si single crystals were grown for the first time from the highly isotopic enriched starting material. Si crystal growth from extremely small charge (the weight of 29Si and 30Si was 4,0g and 13,3g, respectively) was realized by mini‐Czochralski technique (mini‐CZ) which allowed the stable growth conditions during the whole growth process and practically complete volume of the melt was crystallized. To avoid the isotopic dilution SiC seed was used for the growth of 29Si.
Czochralski growth of doped germanium with an applied rotating magnetic field
Authors: Dold P. 
Published: July 2003

AbstractThe influence of time‐dependent buoyancy convection on the temperature field and the microsegregation during the Czochralski growth of doped germanium was investigated. For physical modelling, experiments with gallium melts have been carried out in the temperature range of 690 to 1000 °C. Growth experiments were performed in a 2 inch crucible. Temperature measurements in the melt revealed convective temperature fluctuations in the range of 1.5 K with a standard deviation of σ=0.3 K. The corresponding frequencies are f≤0.6 Hz. The facility was equipped with a rotating magnetic field (RMF) of Bmax=0.8 mT, adjustable in the range of 5 to 400 Hz. When the maximum field strength was applied, a uniform, azimuthal flow was induced and the germanium melt rotates with 60 rpm. The melt rotation generated by the RMF can completely replace crystal and/or crucible rotation. Growth under an applied RMF results in the lowest microsegregation, compared to the growth without magnetic field / without rotation or to the case when the crystal was rotated but no magnetic field was applied. Increasing the magnetic field strength continuously, the convective temperature fluctuations pass through an intermediated state, where their amplitude becomes even higher, before they are effectively reduced by the RMF.
Melt‐crucible wetting behavior in semiconductor melt growth systems
Authors: Cröll A. , Lantzsch R. , Kitanov S. , Salk N. , Szofran F. R. , Tegetmeier A. 
Published: July 2003

AbstractThe wetting angles of several semiconductor‐substrate combinations that are of practical importance for crystal growth have been measured: Ga‐GaSb‐Sb on fused quartz; Ge on fused quartz and carbon‐based substrates, each with a selection of roughness; Si on fused quartz plates and on plates coated with fused quartz, Si3N4, and BN powders. The Ga‐GaSb‐Sb system showed no significant dependence of the wetting angle on the composition despite a large composition dependence of the surface tension. For Ge, the effect of the roughness on the angle could initially be seen on both types of substrates, but for the fused quartz substrates an equilibrium value independent of the surface treatment was reached after several hours of contact time. For Si, total wetting was found for Si3N4 powders. A reduction of the angle over time was found for both fused quartz and BN powders, with the BN powder showing the highest angle at 150‐120°.
Diffusion effects at the Au/p‐CuInSe2 contact studied by XPS
Authors: Neumann H. , Yakushev M. V. , Tomlinson R. D. 
Published: July 2003

AbstractX‐ray excited photoelectron spectroscopy (XPS) was used to investigate the reactions at the interface between Au and CuInSe2 in case of Au/p‐CuInSe2 contacts produced by a procedure usually used to prepare low resistance ohmic contacts. Formation of an In‐Au alloy is observed after an annealing step at 300 °C in a nonoxidising atmosphere. Furthermore, it is found that some amount of gold diffuses into the CuInSe2 substrate. A tentative defect model is proposed to describe the formation mechanism of Au/ p‐CuInSe2 contacts.
In situ study of the kinetics of displacement of growth steps on {010} faces of potassium acid phthalate single crystals grown from aqueous solutions
Authors: Sangwal K. , Wójcik K. , Borc J. 
Published: July 2003

AbstractExperimental results of an in situ study of displacement rates of growth steps, observed by optical microscopy, of different height on the {010} faces of potassium acid phthalate single crystals from aqueous solutions of predefined supersaturations up to 8.5% at about 30 °C are reported and discussed. It was found that: (1) there is a large spread in the displacement rate of steps even for the same supersaturation but the spread decreases with increasing value of supersaturation, (2) in some cases the step displacement rate decreases while in others it increases with increasing growth duration, (3) the average displacement rate of low‐height steps increases linearly with an increase in supersaturation, and (4) the velocity of steps decreases with an increase in their height. Analysis of the results showed that (1) the linear supersaturation dependence of step velocity occurs in the case of a supersaturation independent activation energy for growth, and (2) the supersaturation dependence of relative decrease in the velocity of steps with their height may be explained by three approaches: (i) net flux of growth units from the surface terrace to the advancing step, (ii) time dependent adsorption of solute molecules to the advancing step, and (iii) anisotropy in solute transport by surface diffusion to a step from the two terraces on its either sides (Schwoebel effect). In approaches (i) and (ii) the decrease in the step velocity is associated with the nucleation of kinks on step edges.
Noise thermometry in crystal growth facilities for the International Space Station (ISS)
Authors: Stenzel Ch. , Meyer Th. , Krause H. , Brixy H. 
Published: July 2003

AbstractAlthough noise thermometry is an established technique for absolute temperature measurement, several aspects needed to be clarified before this method can be employed for temperature measurement in a space furnace at 1800°C. First, the electrical insulation resistance for sheathed sensors with different insulation materials were measured. Five test sensors with outer diameters of 3.2 mm or less were fabricated and tested. The measurements clearly show a significant advantage for the pyrolytic boron nitride (pBN) insulation compared to Hafnium oxide. The electrical insulation resistance values at 1800°C for the sensors with HfO2 were below 10 Ω, whereas pBN‐insulated test sensors exhibited values of more than 600 Ω for the same diameter. Furthermore, no difference has been found between the resistance of bent and straight sensors. Based on these results a miniaturised and bent noise thermometer with a diameter of 3.2 mm having a pBN insulation was fabricated. This sensor and additional control thermocouples were subjected to performance tests up to 1800°C in a space‐compatible furnace. All sensor readings exhibited a consistent figure during the tests. The noise thermometer, however, showed always the highest reading indicating that noise thermometry is an appropriate method for accurate measurements of absolute temperatures, even in the harsh environment of a compact multi‐zone space furnace.
Investigation of additional convective transports in liquid metals and semiconductors during diffusion measurements by means of the shear cell technique
Authors: Müller H. , Müller‐Vogt G. 
Published: July 2003

AbstractDiffusion measurements of metallic and semiconductor melts on earth show highly irreproducible results due to occurrence of unknown convection. Therefore we investigated the influence of different kinds of additional transports. Diffusion experiments with the shear cell technique and numerical simulations have been performed. It could be shown that neither the initial transport due to the shearing at the beginning of an experiment nor the buoyancy driven convection due to horizontal temperature gradients have sufficient strength to explain the high scattering of the experimental results. Instead there is strong evidence that solutal Marangoni convection, if free surfaces cannot be avoided, may be the main reason for the irreproducibility, at least under laboratory conditions.
Numerical study of the effects of cusp‐shaped magnetic fields and thermal conductivity on the melt‐crystal interface in CZ crystal growth
Authors: Kakimoto Koichi , Liu Lijun 
Published: July 2003

AbstractA numerical study was carried out to determine the effects of magnetic fields and thermal conductivity of a crystal on the melt flow in a crystal growth system. Comparisons of computations for the case of no magnetic field and for two types of cusp‐shaped magnetic fields were made. The effect of thermal conductivity of a crystal on the shape of a melt‐crystal interface was also investigated. The computation results showed that the magnetic fields have clear effects on both the pattern and strength of flow of the melt and the interface shape. Application of a magnetic field to the Czochralski system is therefore an effective tool for controlling the quality of bulk crystal during Czochralski growth process. The results also showed that the shape of the interface could be modified by changing thermal conductivity of silicon.
Numerical modeling of crystal growth and solidification experiments carried out under microgravity conditions
Authors: Friedrich J. , Dagner J. , Hainke M. , Müller G. 
Published: July 2003

AbstractIn this paper first examples for global thermal modeling of microgravity experiments in the field of crystal growth and alloy solidification are presented. The software program CrysVUn is used to simulate alloy solidification experiments carried out in TEXUS sounding rocket missions. Based on this software global thermal models are developed for the furnace inserts Low Gradient Furnace (LGF) and Solidification and Quenching Furnace (SQF) to be operated in the Materials Science Laboratory (MSL) onboard the International Space Station (ISS). These models will be used in order to optimize the process conditions and cartridge designs for the experiments to be carried onboard the ISS.
An emulation system for melting zone semiconductor single crystal growth in space
Authors: Li Chaorong , Ge Pewen , Pang Yuzhang , Zhai Yongliang , Huo Chongru , Yu Yude , Zhu Zhenhe 
Published: July 2003

AbstractIn situ monitoring and controlling the space experiments is an effective method to enhance the success probabilities of space experiments. A system to emulate the monitoring and controlling process of the semiconductor crystal growth by melting‐zone in space has been built up. The system mainly contains three parts, that are a remote crystal growth furnace, a numerical simulation software package and local controlling and displaying center. The temperature distribution data of the furnace were transmitted to the ground control center for the numerical simulation program as the boundary conditions. The crystal growth process and crystal growth parameters including crystal growth rate, the width of melting‐zone, the shape of the interfaces between crystal and melt, and the temperature gradient at the interface, etc. will be calculated with the simulation program. The theoretical calculation results of the crystal growth process will be then clearly displayed on the ground control terminal with image technique. The growth parameters were also displayed on the screen. Scientists can in situ observe the experiment progress. If the experiment process deviate from the programmed profile, the central control terminal can adjust the heating program of the space furnace to fulfill the requirements. The whole system can successfully emulate the crystal growth process.
Medicines in the 21st century Or pills, politics, potions, and profits: Where is public policy?
Authors: Triggle David J. 
Published: July 2003

AbstractThe delivery of health care over the past century, including drugs for the past 60 years, has brought significant gains to the overall health of the world population. The recent advances in genomics carry the promise, as yet not fulfilled, of far greater benefits perhaps, as far as molecular medicines are concerned of actually delivering Paul Ehrlich's “magic bullet.” However, the delivery of currently available health benefits to the world has been remarkably non‐uniform and the major fraction of the world's population still remains inadequately served by basic public health services, including clean water and sanitation. Additionally, this same population is devastated by diseases including malaria, tuberculosis, and AIDS. This discrepancy in health care parallels the economic disparities that exist between nations and that are in fact increasing rather than decreasing. The absence of health care is a driving force for the generation and maintenance of poverty. The issue is less science than it is public policy and the will of the rich world to generate the infrastructural environments under which the rewards of science can be shared equitably. The delivery of biomedical science in the future is discussed both in terms of the science that will drive advances and the public policy issues that must be implemented to ensure delivery of scientific benefits. Drug Dev. Res. 59:269–291, 2003. © 2003 Wiley‐Liss, Inc.
Origin of group delay ripple in chirped fiber Bragg gratings and its effective reduction method
Authors: Komukai Tetsuro , Inui Tetsuro , Nakazawa Masataka 
Published: July 2003

AbstractIn this paper, the characteristics of a fiber Bragg grating fabricated with a chirped phase mask are compared with those of a fiber Bragg grating that is made chirped by addition of distortion to a uniform fiber Bragg grating without phase error. It is found that the dominant cause of generation of group delay ripples lies in the phase error of the chirped phase mask. It is demonstrated that a chirped fiber Bragg grating with smaller group delay ripples than the conventional ones can easily be obtained by adding linear distortions made of insertion of a rod containing a fiber Bragg grating without phase error into an S‐shaped groove. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 86(8): 76–84, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10007
High‐density 3D packaging sidewall interconnection technology for CCD micro‐camera visual inspection system
Authors: Yamada Hiroshi , Togasaki Takashi , Kimura Masanobu , Sudo Hajime 
Published: July 2003

AbstractThe authors have developed 3D packaging sidewall interconnection technology, which enables a higher packaging density in the 3D stack direction, in order to realize a CCD micro‐camera visual inspection system integrated on the front of an experimental wireless micromachine for a visual inspection robot moving by itself in pipes of diameter 10 mm ϕ in an electric power generation plant. This technology was achieved by exposing the high‐aspect‐ratio circuit wiring layers at the edge of a stack‐unit substrate as sidewall footprint. The sidewall footprint has a high aspect ratio, which is a superior shape for the electrode terminals, by designing the Cu‐filled stacked vias to be laid out directly on the core substrate in a build‐up multilayer wiring substrate. With regard to the alignment between the stack‐unit substrates that determines the relative precision of the sidewall footprint, the process of dividing into the individual 3D packaging modules after multiple‐unit layout stack‐unit substrate lamination was used to improve the precision of sidewall footprint. By using this packaging technology, a prototype 3D packaging module consisting of a CCD video signal transmission circuit and a CCD control signal circuit in a CCD micro‐camera visual inspection system obtained an excellent CCD output signal and confirmed the effectiveness of the technology for high‐density packaging in a microspace. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 86(8): 67–75, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10063