The project involves the development of low pressure chemical vapor deposition and r-f sputtering techniques for the synthesis of single crystal thin films of beta-SiC. The CVD apparatus is being produced in-house and a detailed description of the design is provided herein. Theoretical CVD phase diagrams of the Si-C-H system are also being produced as a function of Si/Si+C and total pressure. Both reactive sputtering of Si in CH4 and normal sputtering of a SiC target are being readied. (Author).

Epitaxial vapor deposition of beta-silicon carbide on (111) beta-silicon carbide platelets and diborane doping were used to grow p-type layers on n-type substrates. Etching and thin film metallizing procedures were developed for silicon carbide, a chlorine-oxygen gas etch at 900 degrees C being used. Specific surface characteristics of solution-grown crystals, epitaxial crystals, and crystals etched in various fluids were correlated with crystal polarity. (Author).

Changes in crystal size and morphology were obtained by modifying the process for growing crystals of betasilicon carbide from solution in carbon-saturated melts. Well developed laths and plates were grown under conditions favoring dendritic growth mechanisms (low thermal gradient with moderate stirring). Polyhedral crystals grew under high thermal gradient conditions when high velocity stirring was employed. Three-dimensionaltype growth was also produced from a 73 wt percent ironsilicon alloy under conditions that normally produce lath-type growth. Uncorrected electron mobilities of 700 to 1000 sq cm/v-sec were measured at room temperature, and a few preliminary Hall measurements were made over the temperature range from 77 to 300 K. (Author).

Beta silicon carbide has the potential of becoming an important semiconductor device material for hazardous military environments such as high temperature and radiation. This report is concerned with a study of the growth of thin single crystal films of beta silicon carbide through molten metal intermediates. Thin films of nickel, cobalt, chromium and iron were deposited by vacuum deposition on to the (0001) faces of single crystals of alpha silicon carbide. Then heteroepitaxial layers of beta silicon carbide were deposited through the molten metal films by the hydrogen reduction of methyltrichlorosilane. The deposited films were studied by electron microscopy, electron diffraction and electron beam microprobe analysis to determine the growth mechanism and to arrive at optimum conditions for heteroepitaxial growth. From the results obtained it was concluded that nickel and cobalt were equally effective in promoting epitaxial growth. Films of nickel only 20A in thickness were as effective as those up to 300A. Results with chromium and iron were disappointing for different reasons. Chromium did not etch the substrate surface uniformly because of poor wetting. With iron, whisker growth of beta silicon carbide occurred at the surface. Although in many respects the growth of mechanism resembled that of the vapor-liquid-solid method, certain differences were observed which make the actual growth mechanism using nickel and cobalt films still uncertain. (Author).

A comprehensive introduction and up-to-date reference to SiC power semiconductor devices covering topics from material properties to applications Based on a number of breakthroughs in SiC material science and fabrication technology in the 1980s and 1990s, the first SiC Schottky barrier diodes (SBDs) were released as commercial products in 2001. The SiC SBD market has grown significantly since that time, and SBDs are now used in a variety of power systems, particularly switch-mode power supplies and motor controls. SiC power MOSFETs entered commercial production in 2011, providing rugged, high-efficiency switches for high-frequency power systems. In this wide-ranging book, the authors draw on their considerable experience to present both an introduction to SiC materials, devices, and applications and an in-depth reference for scientists and engineers working in this fast-moving field. Fundamentals of Silicon Carbide Technology covers basic properties of SiC materials, processing technology, theory and analysis of practical devices, and an overview of the most important systems applications. Specifically included are: A complete discussion of SiC material properties, bulk crystal growth, epitaxial growth, device fabrication technology, and characterization techniques. Device physics and operating equations for Schottky diodes, pin diodes, JBS/MPS diodes, JFETs, MOSFETs, BJTs, IGBTs, and thyristors. A survey of power electronics applications, including switch-mode power supplies, motor drives, power converters for electric vehicles, and converters for renewable energy sources. Coverage of special applications, including microwave devices, high-temperature electronics, and rugged sensors. Fully illustrated throughout, the text is written by recognized experts with over 45 years of combined experience in SiC research and development. This book is intended for graduate students and researchers in crystal growth, material science, and semiconductor device technology. The book is also useful for design engineers, application engineers, and product managers in areas such as power supplies, converter and inverter design, electric vehicle technology, high-temperature electronics, sensors, and smart grid technology.

The report summarizes the development program in the growth of large high purity beta silicon carbide crystals. Conditions for stable beta growth were partially established. Beta silicon carbide can be grown in the region of 2000-2200C and 28-42 microns pressure. Within this region, large beta crystals will grow by sublimation. Lang topographs of crystals were compared with etched surface structures and petrographic examination. Correlation among the results of these techniques was shown to exist. This analysis indicated the presence of large stacking faults within the structure as well as polytype intergrowths. Resistivity and Hall measurements were made with indications of highly compensated material. (Author).

Silicon Carbide — 1968 presents the proceedings of the International Conference on Silicon Carbide held in University Park, Pennsylvania on October 20-23, 1968. The book covers papers about the perspectives on silicon carbide; several problems in the development of silicon carbide semiconductors, such as the control of crystal structure and analysis. The thermal properties of beta-silicon carbide from 20 to 2000 degrees and the influence of impurities on the growth of silicon carbide crystals in chemical reactions and by recrystallization are also discussed. The book then presents papers about silicon carbide single crystal growth using the Norton process; the principles of solution and traveling solvent growth of silicon carbide; the growth of silicon carbide from cobalt-silicon solutions; and the growth of silicon carbide from vapor by the Bridgman-Stockbarger method. Papers about the growth of crystals and epitaxial layers of beta silicon carbide; the heteroepitaxy of beta-silicon carbide employing liquid metals; some aspects of disorder in silicon carbide; and the dependence of physical properties on polytype structure are also considered. The book describes topics about the optical properties of polytypes of silicon carbide as well as the phase stability of silicon carbide against nitrogen. Other papers about the physical and electronic properties of silicon carbide are also discussed in the book. People involved in semiconductor industries will find the book helpful.