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Publication details The article was received on 28 Feb , accepted on 15 Mar and first published on 20 Mar Article type: Paper. DOI: Download Citation: J. High-performance indium phosphide nanowires synthesized on amorphous substrates: from formation mechanism to optical and electrical transport measurements A.
Hui, F. Wang, N. Han, S. Yip, F. Xiu, J. Hou, Y. Yen, T. Hung, Y. Chueh and J. Ho, J. Search articles by author Alvin T. Fengyun Wang. Ning Han. SenPo Yip. Fei Xiu. Jared J. Yu-Ting Yen. TakFu Hung. Yu-Lun Chueh. Research was carried out in two distinct phases. Phase 1 consisted of ultra-high-speed InP epitaxial crystal growth technology development using small prototype metal-organic chemical vapor deposition MOCVD equipment 4x4-inch.
These goals were achieved via a new crystal manufacturing method: carbon-doped indium gallium arsenide InGaAs growth without hydrogen. Marktech says that its evaluation of the small MOCVD prototype derived from this equipment demonstrated favorable performance characteristics. It then performed high-frequency HBT electrical characterization on the prototype with equally favorable results.
Very often, the similar behavior of various ELO structures reveals that the phenomena presented are not related to a specific group of compounds or their growth techniques, but have a much more general nature. The performance of many electronic and optoelectronic devices critically depends on the structural quality and homogeneity of the base material, which is often an epitaxial film grown by either.
Instead, some of the most relevant literature references are given in the historical overview, which also provides a very good insight into the potential of LPE growth of newer materials. Despite the fact that LPE growth has gained less attention over the past decades, mainly due to the development of VPE growth techniques, there is a silver lining which clearly indicates that the highest-quality epitaxial films, for most efficient electronic and optoelectronic devices, will ultimately be achieved from liquid-assisted or LPE-grown films.
Its bandgap is easily tunable over the entire IR range with only very small changes in lattice constant, offering the possibility of multilayer device structures and thus an unlimited choice of device designs, and it yields devices with quantum efficiencies as high as 0. Despite a number of unresolved challenges in achieving its ultimate promise for industrial application, the great achievements in the MBE growth of HgCdTe are made evident by its routine use in the industrial manufacture of focal-plane arrays FPAs.
MBE growth can be continuously monitored in situ by reflection high-energy electron diffraction, spectroscopic ellipsometry SE , and other characterization tools, providing instantaneous feedback on the influence of growth conditions on film structure. This allows the growth of a large range of unique structures such as superlattices SLs , quantum well devices, lasers, and advanced design devices such as multicolor and high-operating-temperature IR sensors and focal-plane arrays.
The growth hardware is discussed very briefly in Sect. A discussion of the doping of HgCdTe, including the serious issues still surrounding p-type doping, is given in Sect. Metalorganic vapor-phase epitaxy offers the ability for controlled layer deposition down to the monolayer range. Versatile application in a wide range of materials and its upscaling ability has established this growth technique in industrial mass production, particularly in the field of semiconductor devices. A topic of current research is the extension of the well-developed GaAs-based technology to the near-infrared spectral range for optoelectronic applications.
The complementary approaches of either employing dilute nitrides quantum wells or quantum dots have recently achieved significant advances in the field of laser diodes. From the point of view of device applications, both pseudomorphic growth and strain-relaxed growth are important. Not only the layer growth but also dot formation is now attracting much attention from both the scientific community and for device applications.
Comprehensive studies on the growth mechanisms have resulted in the development of novel formation techniques of SiGe heterostructures and enable us to implement strain effects in Si devices. It is obvious that the device applications largely depend on the material growth, particularly control of surface reaction and formation of dislocations and surface roughness that strongly affect device performances.
Here we review the fabrication technology of SiGe heterostructures aiming at growth of high-quality materials. The relaxation of strain of SiGe buffer layers grown on Si substrates is discussed in detail, since many devices are formed on the strain-relaxed buffer layers that are sometimes called. Carbon incorporation and dot formation that are now studied to extend the possibilities of SiGe are discussed in this chapter too. Deposition techniques enabling energy control can effectively manipulate the microstructure of the film and tune the resulting mechanical, electrical, and optical properties.
At the high power densities used for depositing stoichiometric films in the. To overcome this problem and to facilitate particle energy transformation from the original as-ablated value to the optimal value for film growth, one needs to carefully select the ablation conditions, conditions for material flux propagation through a process gas, and location of the growth surface substrate within this flux.
In this chapter, we discuss the evolution of the material particles energetics during the flux generation and propagation in PLD and PED, and identify critical control parameters that enable optimum thin-film growth. As an example, growth optimization of epitaxial GaN films is provided. Some examples include wide-bandgap materials such as SiO. PLD—PED systems enable in situ deposition of a wide range of materials required for exploring the next generation of complex structures that incorporate metals, complex dielectrics, ferroelectrics, semiconductors, and glasses.
Convection in the melt can be induced by buoyancy force, rotation, surface tension gradients, etc. The dominant convection mode is also different for different growth configurations and operation conditions. Due to the complexity of the hydrodynamics, the control of melt convection is nontrivial and requires a better understanding of the melt flow structures. Finding a proper growth condition for optimum melt flow is difficult and the operation window is often narrow. Therefore, to control the convection effectively, external forces, such as magnetic fields and accelerated rotation, are used in practice.
In this chapter, we will first discuss the convections and their effects on the interface morphology and segregation for some melt growth configurations. The control of the flows by external forces will also be discussed through some experimental and simulation results. Good understanding of transport phenomena in vapor deposition systems is critical to fast and effective crystal growth system design.
Transport phenomena are complicated and are related to operating conditions, such as temperature, velocity, pressure, and species concentration, and geometrical conditions, such as reactor geometry and source—substrate distance. Due to the limited in situ experimental monitoring, design and optimization of growth is mainly performed through semi-empirical and trial-and-error methods. Such an approach is only able to achieve improvement in the deposition sequence and cannot fulfill the increasingly stringent specifications required in industry.
Numerical simulation has become a powerful alternative, as it is fast and easy to obtain critical information for the design and optimization of the growth system. The key challenge in vapor deposition modeling lies in developing an accurate simulation model of gas-phase and surface reactions, since very limited kinetic information is available in the literature.
The advanced deposition model will be presented for multicomponent fluid flow, homogeneous gas-phase reaction inside the reactor, heterogeneous surface reaction on the substrate surface, heat transfer, and species transport. Thermodynamic and kinetic analysis will be presented for gas-phase and surface reactions, together with a proposal for the reaction mechanism based on experiments.
The prediction of deposition rates is presented. Finally, the surface evolution of film growth from vapor is analyzed for the case in which surface diffusion determines crystal grain size and morphology. Key control parameters for film instability are identified for quality improvement.
Czochralski CZ and float-zone FZ processes. Silicon crystals inherently contain various crystallographic imperfections known as microdefects that often affect the yield and performance of many devices.
Preparation and Some Characteristics of Single‐Crystal Indium Phosphide
Hence, quantitative understanding and control of the formation and distribution of microdefects in silicon crystals play a central role in determining the quality of silicon substrates. These microdefects are primarily aggregates of intrinsic point defects of silicon vacancies and self-interstitials and oxygen silicon dioxide. The distribution of microdefects in a CZ crystal is determined by the complex dynamics, influenced by various reactions involving the intrinsic point defects and oxygen, and their transport. The distribution of these microdefects can also be strongly influenced and controlled by the addition of impurities such as nitrogen to the crystal.
In this chapter, significant developments in the field of defect dynamics in growing CZ and FZ crystals are reviewed. The breakthrough discovery of the. Deeper insight into the formation and growth of microdefects was provided in the last decade by various treatments of the aggregation of oxygen and the intrinsic point defects of silicon.
In particular, rigorous quantification of the aggregation of intrinsic point defects using the classical nucleation theory, a recently developed lumped model that captures the microdefect distribution by representing the actual population of microdefects by an equivalent population of identical microdefects, and another rigorous treatment involving the Fokker—Planck equations are discussed in detail. The industrially significant dynamics of growing CZ crystals free of large microdefects is also reviewed.
Under the conditions of large microdefect-free growth, a moderate vacancy supersaturation develops in the vicinity of the lateral surface of a growing crystal, leading to the formation of oxygen clusters and small voids, at lower temperatures. The vacancy incorporation near the lateral surface of a crystal, or the. A review of CZ defect dynamics with a particular focus on the growth of large microdefect-free crystals is presented and discussed.
Dislocations are a major impediment to the usage of III—V and other compound semiconductor crystals in electronic, optical, and other applications. This chapter reviews the origins of dislocations in melt-based growth processes and models for stress-driven dislocation multiplication. These models are presented from the point of view of dislocations as the agents of plastic deformation required to relieve the thermal stresses generated in the crystal during melt-based growth processes.
Consequently they take the form of viscoplastic constitutive equations for the deformation of the crystal taking into account the microdynamical details of dislocations such as dislocation velocities and interactions.
Semiconductors and Semimetals: Indium Phosphide : Crystal Growth and Characterization (Vol. 31)
The various aspects of these models are dealt in detail, and finally some representative numerical results are presented for the liquid encapsulated Czochralski LEC growth of InP crystals. In this chapter several mathematical models describing processes which take place in the Bridgman—Stockbarger BS and edge-defined film-fed growth EFG systems are presented.
Predictions are made. First, a short description of the real processes which are modeled is given, along with the equations, boundary conditions, and initial values defining the mathematical model. After that, numerical results obtained by computations in the framework of the model are provided, making a comparison between the computed results and those obtained in other models, and with the experimental data. X-ray scattering analysis and instrumentation has been evolving rapidly to meet the demands arising from the growth of sophisticated device structures.
X-ray scattering is very sensitive to composition, thickness and defects in layered structures of typical present-day electronic device dimensions. Considerable information can be obtained from simple profiles, including an estimate of layer thickness and composition by measuring peak separations and a measure of the sample quality from the peak broadening. The full simulation of the profiles takes this a stage further to interpret very complex structures and obtain more reliable parameter estimates. By obtaining two-dimensional scattering data the information becomes more extensive, including layer strain relaxation and defect analysis, quantum dot composition and shape.
Generally the data is averaged over a few mm, however reducing the beam size can break this averaging to reveal inhomogeneities, isolating small regions and in some circumstances isolate individual quantum dots for analysis. This article gives an overview of the status, differentiating those methods that are easily accessible and those that require a collaborative approach because they are still being established. From the first x-ray diffraction image, recorded by Berg in , to the double-crystal technique developed by Bond and Andrus in and the transmission technique developed by Lang in through to present-day synchrotron-radiation-based techniques, x-ray topography has evolved into a powerful, nondestructive method for the rapid characterization of large single crystals of a wide range of chemical compositions and physical properties, such as semiconductors, oxides, metals, and organic materials.
Different defects are readily identified through interpretation of contrast using well-established kinematical and dynamical theories of x-ray diffraction. This method is capable of imaging extended defects in the entire volume of the crystal and in some cases in wafers with devices fabricated on them. It is well established as an indispensable tool for the development of growth techniques for highly perfect crystals for, e. The capability of in situ characterization during crystal growth, heat treatment, stress application, device operation, etc.
Results are presented for the classical orthodox method used for revealing dislocations in Sect. More recently developed open-circuit photo etching approaches, sensitive to both crystallographic and electrically active inhomogeneities in semiconductors, are reviewed in Sect.
In particular, attention will focus on newly introduced etchants and etching procedures for wide-bandgap semiconductors. TEM not only provides very high spatial resolution for the characterization of microstructure and microchemistry but also elucidating the mechanisms controlling materials properties. The results of TEM analyses can also shed light on possible ways for improving the crystal quality. Most TEM studies are carried out in a static status; however, dynamic studies using in situ heating, in situ stressing, and even in situ growth can be conducted to study the development, interaction, and multiplication of defects.
Unfortunately, this powerful tool has faded from the literature in recent years. The present trend away from fundamental studies and towards technological challenges, and the need for fast diagnostic tools for use during and after materials growth has weakened the popularity of magnetic resonance tools. While admittedly the use of EPR in industrial laboratories for routine materials characterization is limited, EPR spectroscopy can be, and has been, successfully used to provide reams of information directly relevant to technologically significant materials.
The interpretation of EPR spectra involves an understanding of basic quantum mechanics and a reasonable investment of time. Once a defect is identified, however, the spectra may be used as a fingerprint that can be used in additional studies addressing the chemical kinetics, charge transport, and electronic energies of the defect and surrounding lattice.
Numerous examples are provided in this chapter.
In addition, the fundamental information extracted from EPR analysis should not be forgotten. We must remember that the basic understanding of semiconductors developed in the middle of the last century spawned the solid-state transistor, which unquestionably produced the computer revolution in the latter half of the 20th century. This chapter will acquaint the reader with the fundamental methods used to interpret EPR data and summarize many different experiments which illustrate the applicability of the technique to important materials issues.
This chapter gives an introduction to the principles of the positron annihilation techniques and then discusses the physics of some interesting observations on vacancy defects related to growth and doping of semiconductors. The role of vacancies in the electrical deactivation of dopants is discussed in Sect. Nowadays, advances in genomics as well as in proteomics have produced thousands of new biological macromolecules for study in structural biology, biomedicine research, and drug design projects.
Novel and classical methods of protein crystallization as well as modern techniques for two-dimensional 2-D and three-dimensional 3-D characterization of different biomolecules are reviewed in this chapter. Production of high-quality single crystals will be analyzed in detail from classical approaches to modern, high-throughput crystal growth methods for x-ray diffraction, as will new strategies for reducing the amount of raw materials used, accelerating the work, and increasing success rates.
It will be pointed out that this work on crystallization as well as characterization is multidisciplinary. These scientific efforts are also interrelated and require close collaboration between biochemists, biophysicists, microbiologists, and molecular biologists, as well as physicists and engineers to develop new strategies and equipment for structural purposes. Finally, some of the problems faced and plans for solving them by using x-ray diffraction, neutron diffraction, and electron microscopy will be revised. Among the various crystallization techniques, crystallization in gels has found wide applications in the fields of biomineralization and macromolecular crystallization in addition to crystallizing materials having nonlinear optical, ferroelectric, ferromagnetic, and other properties.
Furthermore, by using this method it is possible to grow single crystals with very high perfection that are difficult to grow by other techniques. The gel method of crystallization provides an ideal technique to study crystal deposition diseases, which could lead to better understanding of their etiology. This chapter focuses on crystallization in gels of compounds that are responsible for crystal deposition diseases.
The introduction is followed by a description of the various gels used, the mechanism of gelling, and the fascinating phenomenon of Liesegang ring formation, along with various gel growth techniques. The importance and scope of study on crystal deposition diseases and the need for crystal growth experiments using gel media are stressed. The various crystal deposition diseases, viz. Brief accounts of the theories of the formation of urinary stones and gallstones and the role of trace elements in urinary stone formation are also given. The crystallization in gels of 1 the urinary stone constituents, viz.
The effect of various organic and inorganic ions, trace elements, and extracts from cereals, herbs, and fruits on the crystallization of major urinary stone and gallstone constituents are described. In addition, tables of gel-grown organic and inorganic crystals are provided. This chapter describes the types of x-ray detectors, in situ cells, and detectors used in such studies. The procedures are illustrated by a study of the preparation of a tunnel-structured sodium titanium silicate, the partially niobium framework phase, and the mechanism of ion exchange as revealed by time-resolved x-ray data.
Wide-bandgap semiconductor or insulator materials with a high degree of structural perfection are suitable for this purpose. Generated ultraviolet UV or visible light can then be detected at high sensitivity by conventional solid-state semiconductor- or photomultiplier-based photodetectors, which are an indispensable part of scintillation detectors. An insight into this field will be provided for a wider scientific audience and at the same time we will point out some current hot topics.
After reviewing the historical issues and fundamental physical processes of the x. An overview of selected modern single-crystal and optical ceramic materials will be given. Particular attention will be paid to the relation between the manufacturing technology used and the occurrence of material defects and imperfections.
The study and understanding of related trapping states in the forbidden gap and their role in the energy transfer and storage processes in the material will be shown to be of paramount importance for material optimization. Correlated experiments of time-resolved luminescence spectroscopy, wavelength-resolved thermally stimulated luminescence, and electron paramagnetic resonance offer a powerful tool for this purpose.
Future prospects and directions for activity in the field will be briefly mentioned as well. This chapter chronicles those developments and serves as an up-to-date guide to silicon photovoltaic technology. Following an introduction to the technology in Sect. Finally, a perspective on the technology and what might be expected in the future is summarized in Sect. Wafer manufacturing or wafer production refers to a series of modern manufacturing processes of. The majority of wafers are single-crystalline silicon wafers used in microelectronics fabrication although there is increasing importance in slicing poly-crystalline photovoltaic PV silicon wafers as well as wafers of different materials such as aluminum oxide, lithium niobate, quartz, sapphire, III—V and II—VI compounds, and others.
Slicing is the first major post crystal growth manufacturing process toward wafer production. The modern wiresaw has emerged as the technology for slicing various types of wafers, especially for large silicon wafers, gradually replacing the ID saw which has been the technology for wafer slicing in the last 30 years of the 20th century.
Modern slurry wiresaw has been deployed to slice wafers from small to large diameters with varying wafer thickness characterized by minimum kerf loss and high surface quality. In this chapter, advances in technology and research on the modern slurry wiresaw manufacturing machines and technology are reviewed. Fundamental research in modeling and control of modern wiresaw manufacturing process are required in order to understand the cutting mechanism and to make it relevant for improving industrial processes.
To this end, investigation and research have been conducted for the modeling, characterization, metrology, and control of the modern wiresaw manufacturing processes to meet the stringent precision requirements of the semiconductor industry. Research results in mathematical modeling, numerical simulation, experiments, and composition of slurry versus wafer quality are presented.
Summary and further reading are also provided. Springer Professional. Back to the search result list. Table of Contents Frontmatter. Crystal Growth Techniques and Characterization: An Overview A brief overview of crystal growth techniques and crystal analysis and characterization methods is presented here. The starting point is the equilibrium of an infinitely large crystal and a crystal with a finite size with their ambient phase.
- Preparation and Some Characteristics of Single‐Crystal Indium Phosphide.
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- Indium phosphide;
- Progress in Crystal Growth and Characterization of Materials - Editorial Board?
The effect of surface-active species on the rate of nucleation is nucleation at surface explored. This generation of defects propagation of defects chapter presents a review of the typical growth defects of crystals fully grown on planar habit faces, i. The origins and typical configurations of defects developing during growth and after growth are illustrated by a series of selected x-ray diffraction topographs Lang technique and, in a few cases, by optical photographs.