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Book The Feasibility of Liquid Phase Electroepitaxial Growth of Cadmium Zinc Telluride

Download or read book The Feasibility of Liquid Phase Electroepitaxial Growth of Cadmium Zinc Telluride written by Neil Alexander Armour and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Simulation and Growth of Cadmium Zinc Telluride from Small Seeds by the Travelling Heater Method

Download or read book Simulation and Growth of Cadmium Zinc Telluride from Small Seeds by the Travelling Heater Method written by Jordan Douglas Roszmann and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The semiconducting compounds CdTe and CdZnTe have important applications in high-energy radiation detectors and as substrates for infrared devices. The materials offer large band gaps, high resistivity, and excellent charge transport properties; however all of these properties rely on very precise control of the material composition. Growing bulk crystals by the travelling heater method (THM) offers excellent compositional control and fewer defects compared to gradient freezing, but it is also much slower and more expensive. A particular challenge is the current need to grow new crystals onto existing seeds of similar size and quality. Simulations and experiments are used in this work to investigate the feasibility of growing these materials by THM without the use of large seed crystals. A new fixed-grid, multiphase finite element model was developed based on the level set method and used to calculate the mass transport regime and interface shapes inside the growth ampoule. The diffusivity of CdTe in liquid tellurium was measured through dissolution experiments, which also served to validate the model. Simulations of tapered THM growth find conditions similar to untapered growth with interface shapes that are sensitive to strong thermosolutal convection. Favourable growth conditions are achievable only if convection can be controlled. In preliminary experiments, tapered GaSb crystals were successfully grown by THM and large CdTe grains were produced by gradient freezing. Beginning with this seed material, 25 mm diameter CdTe and CdZnTe crystals were grown on 10 mm diameter seeds, and 65 mm diameter CdTe on 25 mm seeds. Unseeded THM growth was also investigated, as well as ampoule rotation and a range of thermal conditions and ampoule surface coatings. Outward growth beyond one or two centimeters was achieved only at small diameters and included secondary grains and twin defects; however, limited outward growth of larger seeds and agreement between experimental and numerical results suggest that tapered growth may be achievable in the future. This would require active temperature control at the base of the crystal and reduction of convection through thermal design or by rotation of the ampoule or applied magnetic fields.

Book The Chemistry of Zinc Telluride and Cadmium Zinc Telluride Metalorganic Vapor phase Epitaxy

Download or read book The Chemistry of Zinc Telluride and Cadmium Zinc Telluride Metalorganic Vapor phase Epitaxy written by Kerri June Wilkerson and published by . This book was released on 1996 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Metalorganic Vapor Phase Epitaxial Growth of 211 B Cadmium Telluride

Download or read book Metalorganic Vapor Phase Epitaxial Growth of 211 B Cadmium Telluride written by Sunil Rao and published by . This book was released on 2009 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Liquid Phase Epitaxial Growth of Hg 1 x Cd x Te from Te rich Solutions

Download or read book Liquid Phase Epitaxial Growth of Hg 1 x Cd x Te from Te rich Solutions written by T. C. Harman and published by . This book was released on 1981 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Strategic Approaches Towards Solving Critical Challenges in Crystal Growth of Detector Grade Cd0 9Zn0 1Te Including Melt Mixing Techniques

Download or read book Strategic Approaches Towards Solving Critical Challenges in Crystal Growth of Detector Grade Cd0 9Zn0 1Te Including Melt Mixing Techniques written by Amlan Datta and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the last few decades Cadmium Zinc Telluride (CZT) has emerged as a novel material for radiation detection in homeland security as well as medical applications and as substrates for epitaxial growth of infrared detector, Mercury Cadmium Telluride. There are, however, several critical issues regarding the bulk growth of CZT which renders it unsuitable or cost ineffective for these applications. These challenges can be summarized as non-uniformity (due to Zinc and intentional dopant segregation), longer growth times (because of lower thermal conductivity of the melt), Tellurium (Te) secondary phases (SP), unstable growth interface (due to lower thermal conductivity and higher heat of fusion) and non-stoichiometric growth conditions. Systematic approaches towards solving these problems will be discussed along with the consequences and future research directions.

Book Large Volume Single Crystal Growth of Cadmium Zinc Telluride with Minimal Secondary Phases for Room Temperature Radiation Detector Application

Download or read book Large Volume Single Crystal Growth of Cadmium Zinc Telluride with Minimal Secondary Phases for Room Temperature Radiation Detector Application written by Santosh Kumar Swain and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Two major aspects of Cadmium Zinc Telluride (CdZnTe) crystal growth for room temperature radiation detection application namely tellurium rich second phase defects and single crystal yield have been addressed. Various approaches were considered towards the minimization of these defects both during growth and post growth thermal treatment in cadmium environment. Since the issue of retrograde solubility in CdZnTe pseudo binary alloy system causes tellurium precipitation, different cooling mechanisms were also devised to achieve minimal secondary phases. Some important and encouraging results were obtained relative to the size and distribution of secondary phases upon growing the crystal with different growth rate and different cooling rate of the crystal after growth. Thermomigration of tellurium were also observed while post processing samples in a temperature gradient, in (Cd, Zn) atmosphere. Results indicated orders of magnitude reduction on secondary phases at the expense of sample resistivity.

Book Surface Structure and Chemistry in the Epitaxial Growth of Cadmium Telluride on Silicon

Download or read book Surface Structure and Chemistry in the Epitaxial Growth of Cadmium Telluride on Silicon written by and published by . This book was released on 2008 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this project was to obtain an atomic-scale understanding of the surface processes that underlie the growth by molecular beam epitaxy (MBE) of HgCdTe on As-passivated Si surfaces. It is generally recognized that in MBE the first few monolayers determine the quality and structure of the final crystalline film. In principle, the methods of surface science can provide the critically needed information about the initial stages of film growth. However, because of the volatile and toxic nature of As and CdTe, special equipment had to be constructed before the deposition processes could be studied. The resulting unique apparatus allowed us to deposit As and CdTe onto Si substrates in a separate preparation chamber with subsequent transfer under vacuum into the main analysis chamber. We used the apparatus to characterize As on several different Si surfaces with the techniques of scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), and Low Energy Electron Diffraction (LEED). The surface analyses were performed with instrumentation that was nearly twenty years old, which slowed progress due to the need for frequent and difficult repairs. Unanticipated budget cuts also impeded progress. Nevertheless, several conference presentations and publications resulted from this work.

Book Molecular Beam Epitaxial Growth of High Quality Cadmium Telluride on Silicon

Download or read book Molecular Beam Epitaxial Growth of High Quality Cadmium Telluride on Silicon written by Yuanping Chen (Ph. D.) and published by . This book was released on 1995 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Liquid Phase Epitaxial Growth of Znx subscript X Cd1x subscript X SnP2

Download or read book Liquid Phase Epitaxial Growth of Znx subscript X Cd1x subscript X SnP2 written by Gary A. Davis and published by . This book was released on 1981 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Chemical Polishing of Cadmium Zinc Telluride CdZnTe and Cadmium Telluride CdTe for Molecular Beam Epitaxy MBE Applications

Download or read book Chemical Polishing of Cadmium Zinc Telluride CdZnTe and Cadmium Telluride CdTe for Molecular Beam Epitaxy MBE Applications written by Saketh Kakkireni and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: