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PAPERBACK list:$19.00 Web:$17.10 add to cart PDF BOOK your price: $15.00 add to cart Rights & Permissions Free Resources PDF EXECUTIVE SUMMARY Display this book on your site! Related Titles Plasma Science: Advancing Knowledge in the National Interest Condensed-Matter and Materials Physics: The Science of the World Around Us Other Related Titles Beam Technologies for Integrated Processing (1992) National Materials Advisory Board (NMAB) Web Search Builder Use this book's key terms to search within this book, across our collection, or across the Web. Skim This Chapter Skim this chapter and use this chapter's key terms to search within this book. Reference Finder Paste in your own text to find books that relate to your topic. Page 43   E-mail  Facebook  Digg  Stumble  Twitter More The following HTML text is provided to enhance online readability. Many aspects of typography translate only awkwardly to HTML. Please use the page image as the authoritative form to ensure accuracy. 5 BEAM APPLICATIONS IN ENGINEERED MATERIALS The application of beam technologies to produce new materials and components, other than microelectronics, is not a new development. This chapter reviews the function of beams in the development of coatings and surface modification and the formation of net shapes, composites, nanophases, and optical surfaces, including treatment of polymeric substrates. New exotic developments in beam processing of materials and some applications for beam technologies also are examined. COATINGS Metal, alloy, and ceramic coatings onto metal, alloy, ceramic, or polymer substrates of various sizes and shapes have been extensively developed and used in the past 30 years. They cover a wide spectrum of applications as summarized in Table 5-1, which lists specific materials and processing methods employed. The techniques used to prepare these materials are classified into two main groups, physical vapor deposition (PVD) and chemical vapor deposition (CVD). These techniques and their applications were discussed previously in Chapter 3. Diamond, Diamond-Like Carbon, And Cubic Boron Nitride Coatings Considerable interest has been aroused in the synthesis of diamond films because of their potential applications in microelectronics, optics, and tribology (Spear, 1989). Synthesis of diamond films by a variety of CVD, PACVD, and PVD techniques has been reported. Applications of these coatings have been limited by the inability to deposit films with smooth surface morphology and with desired optical and electrical properties at acceptable deposition rates, and at deposition temperatures low enough to be compatible with ultraviolet (UV) and infrared (IR) materials or with other process steps employed in microelectronics. Some characteristic properties of individual carbon phases are compared in Table 5-2. The type of film deposited depends on the deposition technique. Table 5-3 lists some potential applications of diamond and diamond-like carbon (DLC) films along with the properties required for each application. Single-crystal diamond films have application for microelectronic and optoelectronic devices. Their high thermal conductivity makes them a candidate for heat sinks, and their electronic properties make them a candidate material for high-power microwave-and millimeter-wave devices and as heat sinks for various high-power devices. Moreover, their large bandgap (about 5.45 eV) can be used to make a variety of UV detectors, and their high resistivity makes possible low-noise UV detectors. Finally, because of their high hardness, there is great interest in tribological applications, such as cutting tools, except for the cutting of steel, where solution of the carbon into the steel can occur. In 1991, several companies have put on the market diamond-coated cutting tools for machining aluminum alloys and polymer-based composites. Page 43 FRONT MATTER (R1-R12) 1 INTRODUCTION (1-2) 2 SUMMARY AND RECOMMENDATIONS (3-8) 3 BEAM TECHNOLOGIES (9-32) 4 BEAM APPLICATIONS IN MICROELECTRONICS (33-42) 5 BEAM APPLICATIONS IN ENGINEERED MATERIALS (43-70) 6 INTEGRATED PROCESSING (71-80) 7 REQUIREMENTS AND PROBLEMS FOR FURTHER INTEGRATION (81-84) APPENDIX A: ACRONYMS AND ABBREVIATIONS (85-86) APPENDIX B: BIOGRAPHICAL SKETCHES OF COMMITTEE MEMBERS (87-89)

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems 5 BEAM APPLICATIONS IN ENGINEERED MATERIALS The application of beam technologies to produce new materials and components, other than microelectronics, is not a new development. This chapter reviews the function of beams in the development of coatings and surface modification and the formation of net shapes, composites, nanophases, and optical surfaces, including treatment of polymeric substrates. New exotic developments in beam processing of materials and some applications for beam technologies also are examined. COATINGS Metal, alloy, and ceramic coatings onto metal, alloy, ceramic, or polymer substrates of various sizes and shapes have been extensively developed and used in the past 30 years. They cover a wide spectrum of applications as summarized in Table 5-1, which lists specific materials and processing methods employed. The techniques used to prepare these materials are classified into two main groups, physical vapor deposition (PVD) and chemical vapor deposition (CVD). These techniques and their applications were discussed previously in Chapter 3. Diamond, Diamond-Like Carbon, And Cubic Boron Nitride Coatings Considerable interest has been aroused in the synthesis of diamond films because of their potential applications in microelectronics, optics, and tribology (Spear, 1989). Synthesis of diamond films by a variety of CVD, PACVD, and PVD techniques has been reported. Applications of these coatings have been limited by the inability to deposit films with smooth surface morphology and with desired optical and electrical properties at acceptable deposition rates, and at deposition temperatures low enough to be compatible with ultraviolet (UV) and infrared (IR) materials or with other process steps employed in microelectronics. Some characteristic properties of individual carbon phases are compared in Table 5-2. The type of film deposited depends on the deposition technique. Table 5-3 lists some potential applications of diamond and diamond-like carbon (DLC) films along with the properties required for each application. Single-crystal diamond films have application for microelectronic and optoelectronic devices. Their high thermal conductivity makes them a candidate for heat sinks, and their electronic properties make them a candidate material for high-power microwave-and millimeter-wave devices and as heat sinks for various high-power devices. Moreover, their large bandgap (about 5.45 eV) can be used to make a variety of UV detectors, and their high resistivity makes possible low-noise UV detectors. Finally, because of their high hardness, there is great interest in tribological applications, such as cutting tools, except for the cutting of steel, where solution of the carbon into the steel can occur. In 1991, several companies have put on the market diamond-coated cutting tools for machining aluminum alloys and polymer-based composites.

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems Table 5-1 Coatings, Depositing Methods, and Applications of Various Beam-Prepared Materials Applications Materials Processes Decorative: on textile fibers, watches, bezels, eyeglass Al Evaporation   TiN, Ti(C,N), Cr3C2, Cr3N2 PAPVD     PAPVD Wear-resistant coatings on cutting tools, dies, punches:     Cement carbide substrates TiC, TiN, Al2O3 CVD   Multilayers PACVD (pilot plant) High-speed steel, die steel substrates TiN, Ti(C,N), Ti, Al, N, TiC PAPVD using electron beam, cathodic arc, and sputtering sources Corrosion-resistant coatings: Steel strip   PVD   Al, Zn, Sn, Cr3N2 High-rate electron beam evaporation   Zn Resistance-heated source Steel fasteners, aircraft parts, etc. Al PAPVD using resistance-heated evaporation sources High-temperature oxidation and corrosion resistance of turbine materials Ni-Co-Cr-Al-Y, Co-Cr-Al-Y, Ni-Cr-Al-Y, Al Electron beam evaporation     CVD Magnetic media on tape Fe, Co, oxides Evaporation, sputtering, oblique incidence evaporation Heat barriers and moisture barrier coatings on polymeric films Al Electron beam evaporation in a continuous or semicontinuous film Optical coatings on polymeric film Various metals, oxides, multilayers Sputter deposition Optical coatings on components such as lenses MgF2, oxides Electron beam evaporation, sputter deposition Optical coatings on glass mirrors, head lamps Al, Ag Evaporation, sputter deposition Photovoltaic solar cells a-Si:H PACVD

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems Table 5-2 Properties of Diamond, Diamond-Like Carbon, and Graphite   Diamond DLC Graphite Crystal structure Cubic Amorphous with small-crystal regions mixed with sp2 and sp3m bondsa Hexagonal   3.567   a = 2.47       c = 6.79d Density (g/cm3) 3.51 1.8-2.0 2.26 Chemical stability Inert, inorganic acids Inert, inorganic solvents, acids Inert, organic acids Hardness (vickers, kg/mm2) 7,000-10,000 + 900-3,000 — Thermal conductivity (cal-cm/cm2-secºC) 20 at 20ºC — Optical Properties Refractive index (n) 2.42 1.8-2.2 Transparency UV-VIS-IR VIS-IR Opaque Optical gap (eV) 5.5 2.0-3.0 — Electrical Properties Resistivity (O;)-cm) >1016 1010-1013 Dielectric constant (e') 5.7 4-9 Dielectric strength (V/cm) >1012 106-1010 — a electronic orbital configuration of the carbon atom b parallel to the "c" axis of the crystal c perpendicular to the "c" axis of the crystal d crystal lattice dimensions in the two axis directions, in Å units

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems Table 5-3 Applications of Diamond and Diamond-Like Carbon Films Application Property Requirement Type of Coating That Could be Used Decorative coatings Hard, transparent in visible range of the spectrum Diamond-like (DLC), small-grain polycrystalline diamond films or DLC amd diamond composite coatings Tribology     Wear-resistant coatings for cutting tools Hard, corrosion resistant, wear resistant and chemically inert Same as above Impact-resistant coatings for cutting tools Very thin films (100 Å) with high hardness, corrosion resistance, and chemical inertness Same as above Optics     Protective coatings for IR optics Hard, corrosion resistant, chemically inert, transparent in IR region Same as above Antireflection Same as above and refractive index coatings for Ge DLC coatings of about 2.0 Protective Layer for solar cells used in space Low radiation damage, transparent in visible range of the spectrum DLC, polydiamond, or composite DLC and diamond X-ray windows Self-standing film with high transmission and low damage threshold for x-rays, smooth surface topography Fine-grained polycrystalline diamond film ELectronic and Optoelectronic     Protective layer for electronic devices, Hard, chemically inert, corrosion resistant, insulating high breakdown voltage DLC, polydiamond, or composite of DLC and diamond Heat sinks for high-power devices Same as above and very high thermal conductivity Polycrystalline diamond Printed circuit boards Same as above Polycrystalline diamond Lasers, UV sensors, etc. Same as above and with stringent requirements on optical bandgap, defect states, surface topography, etc. Large-grain polycrystalline and single crystal-diamond, doped diamond Transistors, high-power devices, IMPATT devices, etc. Same as above, together with stringent requirements on resistivity, dielectric constant, coefficient of thermal expansion, mobility, carrier concentration, etc. Single-crystal diamond (preferably epitaxial diamond) and doped diamond films

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems Diamond films have been prepared by CVD, PACVD, and ion beam deposition techniques. CVD techniques used for the synthesis of diamond films are the chemical transport method, hot-filament thermal CVD techniques, electron-assisted CVD, and flame torch methods. It appears that independent and accurate control of atomic hydrogen in the process environment is key to the deposition of good-quality diamond films. PACVD techniques (with dc, rf, or microwave excitation) have been widely used for the synthesis of diamond and diamond-like carbon coatings. In addition, ion-beam-assisted and low-temperature ARE have been used to prepare diamond films. Recently, small-area diamond single-crystal films have been prepared on a copper substrate that have potential use for microelectronic applications (Narayan et al., 1991). Diamond-like carbon produced by sputter deposition is principally used as a wear-resistant coating for magnetic disks. Some varieties of also are used for coating polymeric eyeglass lenses for abrasion resistance. Cubic boron nitride (CBN), like diamond, is a metastable material at ambient temperatures and pressures. It possesses an attractive combination of properties similar to diamond—high thermal conductivity, high electrical resistivity, very high hardness, chemical inertness, transparency over a wide range of wavelengths, from UV through the visible into the IR, and has a large bandgap. Synthesis of CBN films can be accomplished by various CVD, PACVD, and PACVD techniques, at deposition temperatures from ambient to 1000ºC, depending on the process used. Almost all the reactant species used in CBN synthesis are either toxic or explosive. To avoid this problem, a unique process has been developed using the reaction between nontoxic boric acid and ammonia in a PAPVD process to deposit CBN films at temperatures as low as 400ºC. Unlike diamond films, there is no difficulty in nucleating the material on a variety of substrates. Various applications in tribology, optoelectronics, and microelectronics have been studied. CBN is a very potent competitor to diamond films, and the state of development is considerably advanced. Unfortunately, it lacks the mystique associated with diamond. SURFACE MODIFICATION Two beam techniques are predominant in surface modification of materials; ion implantation and laser treatment. Ion implantation is presently used in a limited but demanding number of high-technology, high-precision, and high-value-added, critical-use applications. The main advantages of ion implantation (Sioshansi, 1989) are flexibility in that any element can be introduced into any substance; no thermodynamic constraints exist, such as the requirement of an elevated temperature for diffusion or initiation of a chemical reaction; no refinishing or reheat-treating of the part is required, since the ion implantation can be performed at or near room temperature; no noticeable change occurs in the dimensional integrity of the part, no shape distortion, and no need for final finishing or polishing of the components; and no discrete interface is produced that can fail, since the ions penetrate into the original surface. The main application of ion implantation to date has been in the treatment of metals. However, in recent years there has been significant interest in the treatment of ceramic and polymer substrates by ion implantation. Table 5-4 shows the variety of materials treated by ion implantation and lists the properties influenced by the process. Many of these have been reviewed recently by Smidt (1990a,b).

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems Table 5-4 Materials Modified by Ion Implantation Material Properties Influenced Benefits Metals Hardness, hard-phase precipitates Wear resistance   Compressive stress, amorphization Low friction, fatigue resistance   Alloy formation, metastable-phase formation Corrosion resistance, oxidation resistance Ceramics Compressive stress, amorphization Improved fracture resistance; fatigue resistance Polymers Cross-linking, carbon-carbon bonds, densification Increased wear and scratch resistance, increased electrical conductivity   Source: Sioshansi, 1988. There are numerous applications in which ion implantation has been tested in fields ranging from aerospace to biomaterials. Table 5-5 lists some successful ion implantation applications. There are many new applications where ion implantation is currently under investigation. These are mainly in areas of changing the optical properties of materials, influencing catalysis of surfaces, creating new magnetic alloys, improving adhesion properties of surfaces, and, finally, improving biocompatibility of materials. These applications are expected to have a significant impact on future trends in surface-engineered components. Laser treatment, since it can be employed in atmosphere or nonvacuum ambients, offers greater flexibility for modifying large, irregular surfaces. Laser beams are being used to harden metal surfaces, and they provide corrosion resistance. In addition, selective etching using lasers is in fairly widespread use (e.g., as a marking tool). Laser welding also is finding application but on a limited basis. The ease of implementing lasers, compared to ion beams, makes this approach particularly suitable for integrated manufacturing. APPLICATIONS OF LASERS TO MATERIALS FORMING The unique features of lasers have led to their use in a variety of shaping operations, including the removal (Copley, 1986) and deposition of materials (Deitz, 1990). They are routinely used for hole drilling and cutting sheets (Steen and Kamalu, 1983) and show promise for use in turning and milling operations (Copley, 1985). Lasers also can be used to build up shapes through processes such as solidification (Breinan et al., 1980), sintering (Deckard and Beaman, 1989), polymerization (Hull, 1986), and in CVD (Osgood et al., 1983). They have been used

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems Table 5-5 Some Successful Ion Implantation Applications Ion Species Material Problem Applications Status Ti+C Ferrous alloys Wear Bearing, gears Production valves, dies Cr Ferrous alloys Corrosion Surgical tools   Ta+C Ferrous alloys Scuffing wear Gears Pilot production P Stainless steels Corrosions Marine products, chemical processing Research C, N Ti alloys Wear, corrosion Orthopedic prostheses, aerospace components Production N Al alloys Wear, mold release Rubber and polymer molds Preproduction evaluation Mo Al alloys Corrosion Aerospace, marine Research N Zirconium alloys Hardness, wear, corrosion Nuclear reactor Chemical processing Production N Hard chrome plate Hardness Valve seats, godets, travellers Pilot production Y, Ce, Al Superalloys Oxidation Turbine blades Research Ti+C Superalloys Wear Spinnerettes Preproduction evaluation Cr Cu alloys Corrosion Battery technology Research B Be alloys Wear Bearings Pilot production N WC+Co Wear Toot inserts, PC board drills Pitot production N, At, Ti, etc. Ceramics Oxidation, wear, toughness Adiabatic engines turbine parts Research Ar, N, etc. Polymers Conductivity Microelectronics Research Ti, Al, etc. Polymers Mechanical properties Aerospace automotive Research   Source: Sioshansi, 1987

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems routinely to build up shapes by welding (Mazumder, 1983) and soldering. The advantages in carrying out any of these processes with a laser in an integrated processing system are short interaction times, the atmosphere may be varied, a high degree of flexibility, and ease of on-line inspection and process control. Shaping And Removal Important issues with respect to many material removal processes are the roughness and cleanliness of the machined surface, the material removal rate, and the strength and toughness of the laser-machined article. These issues, along with those related to process integration, are discussed in this section. Hole drilling and sheet cutting with lasers have proven to be commercially viable processes. In fact, on a dollar basis, sheet metal cutting accounts for the largest fraction of CO2 laser sales. In this application, laser cutting provides an economical alternative to a punch and die for cutting nonstandard shapes in small to moderate size batches. Creating a computerized numerical control program for laser cutting is a much less expensive step than fabricating a punch and die set for press work. Nevertheless, the use of laser cutting in combination with a punch and die to handle standard shapes has proven to be a cost-effective, flexible approach to sheet metal cutting. Both operations are now routinely carried out in series in continuous flow and transfer station systems. Material is removed by melting the substrate and blowing the melt away with an inert gas jet. In some cases a reactive gas jet is used (e.g., oxygen for cutting steel or titanium), where some of the metal burns, and the enthalpy of the oxidation reaction adds to the energy provided by the laser to melt additional material. Excellent edge quality is attained, so that the need for subsequent deburring operations is often eliminated. Because of the speed of the cutting, there is little time for heat transfer to the workpiece, so the heat-affected zone is normally very small. Advantages of laser hole drilling include the capability of drilling fine holes with high aspect ratios, no machining forces are introduced, applicability to a wide range of materials, and adaptability to numerical control. Laser-drilled holes tend to be tapered, and resolidified material, vapor-deposited residues, and (in polymeric materials) charred regions are often observed. Nevertheless, laser hole drilling has been used successfully in a wide variety of applications, including drilling fine holes in diamond dies (e.g., with a ruby laser), cooling holes in nickel-base superalloy turbine blades, perforation of cigarette paper for use with low-tar and low-nicotine filters, and holes in baby bottle nipples. Truly remarkable results have been attained in machining polymeric and organic materials with excimer lasers. A high degree of spatial resolution and excellent surfaces can be attained, even to such accomplishments as holes drilled in a human hair (Znotins et al., 1987). Laser-assisted machining, a form of hot machining, has been used in turning hard-to-machine metallic alloys. In this process the laser heats the material in front of the cutting tool, thereby improving its machinability. Under force-limited cutting conditions, for example, a factor of two increase in material removal rate, without increase in cutting force, has been reported for difficult-to-machine turbine materials, such as Inconel 718 and Ti-6Al-4V. Lasers have also been used to shape hard ceramic materials by ablation. In Si3N4, for example, high material removal rates (1 cm3 in 200 sec) and smooth surfaces (3-µm arithmetic average surface roughness) have been reported for a moderate incident power of 560 W and a scan speed of 240 cm/sec (Wallace and Copley, 1989). Although laser machining causes some loss of strength, it has been shown that this loss can be completely recovered by an inexpensive etching

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems treatment (Tao et al., 1989). In some cases, reactive gases have been used in conjunction with laser ablation to help remove the reaction products, a process called laser-assisted chemical etching. Desktop Deposition There has been considerable interest recently in the concept of ''desktop'' manufacturing, which permits production of a three-dimensional shape in two steps. The first step involves positioning a computer graphics rendering of the shape with respect to coordinate axis and sectioning the shape into thin layers. The second step converts the shape of each layer to a set of instructions that are communicated to a laser that scans a surface so as to reproduce the layer. In one version of this process, the layer is reproduced by selective polymerization by the laser of a layer of liquid resin. In another version the layer is reproduced by selective sintering by the laser of a layer of plastic or wax powder. So far, desktop manufacturing has been mostly applied to plastics and waxes, with considerable success in attaining smooth surfaces and good shape definition (Deitz, 1990). The technique has found application in prototyping and modeling with considerable interest in applying the technique to form waxes for prototype investment castings (ASM International, 1990). There is a possibility that the technique could be extended to structural materials through application of other processes, such as sintering, melting, and laser chemical vapor deposition (LCVD). Joining Lasers have been used with considerable success to produce autogeneous weldments and hard facing and for soldering. The laser's characteristic short interaction times have the beneficial effect of limiting undesirable reactions in the joining of dissimilar metals. POWDER PREPARATION The increasingly stringent requirements on structural and electronic ceramics often cannot be met using traditional mechanically reduced powders. In addition, the increased prominence of covalently bonded ceramics (e.g., SiC and Si3N4) has increased the requirements for nonconventional, highly q powders. The improved powders should include the following characteristics (Bowen, 1980): small particle size, freedom from agglomeration, narrow size range, spherical shape, and highly controlled purity. Such powders can be produced either by liquid (e.g., sol-gel), solid (e.g., decomposition of salts such as carbonates), or vapor-phase techniques. The common theme in all these techniques is that the powders are built up or synthesized rather than broken down or comminuted. The vapor-phase techniques, in general, can be categorized as beam processes and will be considered briefly below. Vapor-phase techniques for powder processing have been described in a number of recent papers (Kato, 1987; Rice, 1987; Marra and Haggerty, 1987). These techniques have a number of potential advantages for the production of closely controlled powders, such as high purity of the product because of the high-purity gaseous reactants, loosely agglomerated powders because of the highly diluted reaction, ultrafine powders with narrow size distributions, and versatility for producing a wide variety of powders, including metals as well as oxide and nonoxide ceramics. In laser processing the gas is heated directly by coupling the emitted photons with the absorption lines of the reactant gas. In an optimized process the efficiency is essentially equal to that for conversion of electrical energy to laser output. Silane (SiH4) absorbs strongly at the 10.6-µm

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems wavelength of a CO2 laser. Thus, silicon, silicon nitride, and silicon carbide are readily synthesized by the following reactions (Cannon et al., 1982): The other reactant gases, such as methane and ammonia, where required, are heated indirectly by collisional processes. Conventional CVD has also been used to produce a wide variety of powders. The key to producing fine powders is the use of a high degree of supersaturation so that homogeneous nucleation occurs. Particle size is determined from the relative nucleation and growth rates, which are controlled by the reaction parameters. Among the powders that have been produced by conventional CVD processes are Si3N4, SiC, TiN, ZrN, VN, TiC, Mo2C, a-Fe2O3, TiO, a-A12O3, ZrO2, and Nb3 Sn (Kato, 1987). Other vapor-phase processes that have been used for powder processing include inductively coupled and microwave plasma systems, steam hydrolysis, chloride oxidation (Johnson, 1987), and high-pressure sputtering (Suh et al., 1991). COMPOSITES FABRICATION Metal-matrix and ceramic-matrix composites, and the ceramic whiskers and fibers on which they are based, are advanced technologies whose applications are just beginning. A variety of innovative processes have been developed for them, many based on beam processing techniques. Vapor deposition techniques, discussed below, have been used to form both the reinforcing whiskers and filaments for metal and ceramic composites, and chemical vapor infiltration of fiber preforms is used for matrix formation in ceramic composites. Recent applications of beam technologies to composites are summarized in Table 5-6. Table 5-6 Summary of Applications of Beam Technologies to Composites Application Process Materials Whisker growth Rice hull pyrolysis ß-SiC Fiber production Vapor-liquid-solid (VLS) ß-SiC, TiC, ZrN, TiN, ZrC Fiber coating Chemical vapor deposition ß-SiC, boron Metal matrix Chemical vapor deposition BN, C, etc. Ceramic matrix Electron beam evaporation Ti-6Al-4V, Ti   Chemical vapor infiltration SiC, Si3N4, A12O3, B4C, TiC, BN, Si

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems Fiber And Whisker Preparation Chemical vapor processing is widely used to produce ceramic whiskers, platelets, and continuous fibers for reinforcement of composites. The chemistry and properties of the fiber-matrix interface are important in developing ceramic-matrix composites, and each interface must be tailored to give a bond strength that is suitable to provide an appropriate toughening mechanism (e.g., to control fiber pullout). CVD is probably the most common method currently used for coating fibers to thicknesses ranging from nanometers to several micrometers to provide an appropriate interface between fibers and matrix (Cranmer, 1989; Kerans et al., 1989). Silicon carbide whiskers are grown today on a commercial basis from the pyrolysis of rice hulls, which are composed mostly of cellulose with hydrated amorphous silica (Lee and Cutler, 1975). Heating rice hulls in a coking furnace at 1200º to 1800ºC causes a reaction between silicon suboxide and carbon via the gas phase to form silicon carbide whiskers (Nutt, 1988). These whiskers currently are finding commercial application as reinforcements in ceramic cutting tools and are being intensively evaluated in structural composites. Vapor-grown particulates, as well as whiskers, have been used as reinforcements in ceramic cutting tools (Rothman et al., 1986; Lee and Borom, 1988). In addition to SiC, whiskers of TiC, ZrN, TiN, and ZrC have been formed by CVD. In each case, the source of carbon was methane, with metal tetrachlorides for the metal ion and nitrogen for the nitride ion. Nickel, palladium, and platinum, among others, were effective for catalytic growth of these whiskers on a mullite procelain (Kato et al., 1977; Kato and Tamari, 1980; Wokulski and Wokulska, 1983). The growth temperature, typically 1100º to 1300ºC, produced whiskers with diameters ranging from 10 to 300 µm and lengths of a few millimeters. The TiC whiskers appear to grow by a vapor-liquid-solid (VLS) mechanism on Ni at the initial stage and by a vapor-solid (VS) mechanism on mullite after the initial stage (Tamari and Kato, 1979). Whisker technology reviewed by Levitt (1970) provides rather extensive coverage of CVD and other growth methods. Catalyzed growth of both carbon and silicon carbide whiskers has been reported. Japanese (Koyama and Endo, 1972, 1983), French (Oberlin et al., 1976), and American (Tibbetts, 1989) investigators have reported the growth of carbon whiskers from metal catalyst particles (usually Fe), of a few nanometers in diameter, exposed to a mixture of hydrocarbon gases and hydrogen at a temperature near 1000ºC. The growth rate may be as high as several millimeters per minute. The filament length is several centimeters, while the whisker diameter remains about the same as the catalyst particle (Tibbetts, 1989). Baker and coworkers have been actively studying the catalyzed growth of carbon filaments using controlled-atmosphere electron microscopy, in which a gas reaction cell is incorporated within an electron microscope (Baker and Harris, 1978). This permits continuous observation of the gas-solid reactions as they occur. A comprehensive review of the literature on the formation of filamentous carbon was published by Baker and Harris (1978). The whiskers can be made thicker by in situ CVD to diameters of 7 to 10 µm and can be grown to several centimeters in length. Strengths of 2.9 GPa (420 Kpsi) and modulus values of 240 GPa (34 Mpsi) have been measured. The whiskers can be given a very high degree of preferred orientation by high-temperature heat treatment to produce a morphology consisting of graphitic "C" planes wrapped around the whisker axis. This configuration gives many unique properties, including exceptionally high thermal conductivity along the whisker axis. A detailed theoretical analysis of the growth process has been presented by Tibbetts (1989).

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems Architectural and automotive films are deposited on windows to control energy transfer within some specified aesthetic or visibility constraint (Granquist, 1989). For maximum reduction of air conditioning loads, high reflectance is needed over both the visible and infrared spectra. For colder climates, however, maximum energy conservation requires high transmission of the solar energy in the visible and near infrared, but high reflectance (low emissivity) in the intermediate infrared to return radiation back into the building. A few examples of such practical optical solutions are given in Table 5-9. Some of these films are routinely manufactured, with annual outputs of over 2 million square meters per system, for use in such volume applications as automobiles and buildings. Table 5-9 Practical Optical Solar Energy Solutions Using Deposited Films Process Material Characteristic Sputtering TiO2:Ag:TiO2 Good visible transmission, good infrared reflection Sputtering, pyrolysis In2O3:Sn, SnO2:F Fair visible transmission, good infrared reflection Sputtering ZnO:Al Good visible transmission, fair infrared reflection Sputtering electron beam, evaporation Noble metals Good infrared reflection Dielectric optical waveguides on substrates (Miller and Kaminow, 1984) are used today chiefly in discrete couplers, which may be directional, star, wave-division multiplexing, or polarization retaining. As optoelectronics evolves, applications may be expected in hybrid circuits. Even with fully integrated circuitry available, some applications for discrete and hybrid components are expected to exist. Planar devices, most amenable to beam processing, compete with discrete couplers made by commercially available bulk methods. Most planar devices are used for research and are made by diffusion, plasma-enhanced CVD, or silica soot (fume) deposition. Microlenses (Iga et al., 1984) also may become part of hybrid circuits; they have been made by diffusion or, as Fresnel lenses, by electron beam machining. Presently, commercial lenses are made by bulk processing. Active dielectric devices in electrooptics include such components as switches, isolators, and spectrum analyzers. Almost all such switches are presently made by diffusing titanium into lithium niobate to make the device structure (Thylen, 1988), but ion implantation has also been used. The titanium provides the refractive index change to create the waveguides within the electrooptic material. These switches have the largest bandwidth from low frequencies of any switch and thus potentially have a broad range of applications. They are presently employed in commercially available equipment for signal processing. Faraday isolators are presently discrete devices, and attempts to make them in a form suitable for integrated optics are still beset with problems.

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems POLYMERS The volume of polymeric substances used in industry is constantly growing, and plastics are used as substitutes for metals in a variety of applications. Beam technologies are responsible for formation of a variety of specialty plastic materials. These technologies are used either for treatment of bulk or surfaces of polymers. The main objectives for treatment of polymers are outlined in Table 5-10. Table 5-10 Objectives for Treatment of Polymers with Beam Technologies Bulk Treatment (beam species) Surface Treatment (beam species) Co-polymerization (electron, gamma) Metallization (PV, PACVD, LCVD) Irradiation (electron, gamma) Surface hardening (ions, PACVD, PVD) Sterilization (electron, gamma, PVD) Chemical resistance (PVD, PACVD, ion) Cutting, shaping, forming (lasers, heat) Gas permeation (ion) Densification (lasers, heat, ion)   MATERIALS FOR ENERGY PRODUCTION The unique ability to tailor the characteristics and properties of materials produced by CVD has led to the use of these materials in a number of advanced energy applications where conventional materials were inadequate. In this sense, CVD has been an enabling technology. The coated-particle nuclear fuel concept is based on CVD of carbon and ceramic coatings on a fuel ''kernel'' in a fluidized bed (Gulden, 1986). One of the most promising concepts for nuclear power in space is in-core thermionics. The heart of this concept is the tungsten emitter produced by CVD. The emitter has a duplex structure with the inner coating, deposited from tungsten hexafluoride, providing strength and creep resistance, and the outer layer, deposited from the chloride, has a (110) texture to provide the maximum electron work function (Yang and Hudson, 1967). The first wall of magnetic confinement fusion devices will require structures with low neutron activation, high melting temperature, and low physical and chemical sputtering rates. "Armor tiles" coated by CVD processes with carbon and refractory ceramic materials have been developed for this application. A codeposited coating of pyrolytic carbon and silicon carbide has proven particularly effective because of its unusually high resistance to chemical sputtering (Hopkins et al., 1984). In situ boron carbide coatings also have been used (Veprek et al., 1989). BIOIMPLANT DEVICES Ion implantation has been shown to be very effective in reducing the wear of titanium-based total joint replacements in the orthopedic field (Sioshansi, 1987). The superior wear resistance results from both increased hardness of the titanium alloy (Ti-6Al-4V) and the lower coefficient of friction from homogenization of the two-phase alloy and formation of nitride, oxide, and carbide precipitates on the surface of titanium components. The new-generation orthopedic implants are manufactured from Ti-6Al-4V alloy for its ideal biocompatibility. The Ti-6Al-4V alloy has a superior corrosion and fatigue resistance compared

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems to the traditional cobalt-chromium-molybdenum alloy and has a lower modulus of elasticity that provides a better match for the bone. In total joint replacement the titanium component articulates against an ultrahigh molecular weight polyethylene (UHMWPE) surface. Improvements in the wear resistance of Ti-6Al-4V are of significant interest to the orthopedic community. Ion implantation of species, such as nitrogen and carbon, into the Ti-6Al-4V component has been shown to increase the microhardness of the alloy (Sioshansi, 1987). A threefold increase in microhardness (at loads of I to 2 g) can easily be achieved in these alloys. Recent work (Sauer, 1986) at MIT has shown that nitrogen implantation into Ti-6Al-4V changes the two-phase microstructure (the appearance of alpha and beta microplates) of the Ti-6Al-4V plates and renders the material impervious to standard etchant solutions. Earlier work showed that a reduction in the coefficient of friction of the Ti-6Al-4V alloy from 0.48 to 0.15 results from nitrogen-ion implantation at 100 keV to a total dose of 4 × 1017 ions/cm2 (Oliver et al., 1984). The increased hardness and lower coefficient of friction in the titanium alloy are believed to be the reason for a lower wear rate of the alloy and a much reduced wear rate of the articulating UHMWPE surface; a 1000-fold reduction has been observed in the corrosive wear of the titanium-polyethylene couple. The significant reduction of the wear of the titanium-UHMWPE system has convinced orthopedic manufacturers to specify this process in treating their products. (IONGUARD is the registered trademark of Spire Corporation, and the 1000 Series is used for processing titanium-based orthopedic implants.) This application has already reached market maturity, and large quantities of titanium-based orthopedic knees and hips and smaller quantities of wrists, shoulders, fingers, and toes are routinely prepared using the ion implantation process. Pyrolytic carbon has been found to be exceptionally biocompatible (Bokros et al., 1972; Humbold et al., 1981). Addition of a few percent SiC in a CVD codeposition process provides the strength and wear resistance required for artificial heart valves (Kaae and Gulden, 1971; Shim and Schoen, 1974). As a result of these unique characteristics, heart valve components coated with carbon and SiC, codeposited by CVD, have come to dominate the artificial heart valve market in the past decade. These materials are also being evaluated for other applications, such as subcutaneous leads, joint replacements, and dental implants. REFERENCES Akimune, Y., Y. Katano, and K. Matoba. 1989. Spherical-Impact Damage and Strength Degradation in Silicon Carbide Whisker/Silicon Nitride Composites. Journal American Ceramic Society 72(5):791-798. ASM International. 1990. Tech Spotlight: Laser-Base Methods Speed Up Modelmaking. Advanced Materials & Processes 138(7):51-53. Baker, R. T. K., and P. S. Harris. 1978. The Formation of Filamentous Carbon. Chemistry and Physics of Carbon. P. L. Walker and P. A. Thrower, eds., Vol. 14 pp. 83-165. Marcel Dekker, New York. Baldoni, J. G., and S. T. Buljan. 1988. Ceramics for Machining. American Ceramic Society Bulletin 67(2):381-387.

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems Bickerdike, R. L., D. Clark, J. N. Easterbrook, G. Hughes, W. N. Mair, P. G. Partridge, and H. C. Ranson. 1984-1985. Microstructures and Tensile Properties of Vapor Deposited Aluminum Alloys. Part I: Layered Microstructures. International Journal Rapid of Solidification 1:305-325. Billman, E. R., P. K. Mehrota, A. F. Shuster, and C. W. Beeghly. 1988. Machining with Al2O3-SiC Whisker Cutting Tools. American Ceramic Society Bulletin 67(6):1016-1019. Bokros, J. C., L. D. LaGrange, and F. J. Schoen. 1972. Control of the Structure of Carbon for Use in Bio-Engineering. Chemistry and Physics of Carbon. P. L. Walker, Jr., ed., Vol. 9. Marcel Dekker, New York. Bowen, H. K. 1980. Basic Research Needs on High Temperature Ceramic for Energy Applications. Materials Science Engineering 44(1):1-56. Breinan, E. M., D. B. Snow, C. O. Brown, and B. H. Kear. 1980. New Developments in Laser Surface Melting Using Continuous Prealloyed Powder Feed. Rapid Solidification Processing. Claitors Publishing, Baton Rouge, LA. Buckley, J. D. 1988. Carbon-Carbon, An Overview. American Ceramic Society Bulletin 67(2):364-368. Buhrmaster, C. L., D. E. Clark, and H. B. Smart. 1988. Spray Casting Aluminum and Al/SiC Composites. Journal of Metals 40(11):44-45. Bunshah, R. F. (ed.) 1982. Deposition Technologies and Their Applications. Noyes Publications, New York. Bunshah. R. F. and C. V. Deshpandey. 1987. The Activated Reactive Evaporation Process. Physics of thin Films 13:59. Academic Press, New York. Bunshah, R. F., and R. S. Juntz. 1965. Electron Beam Distillation Furnace for Reactive Metals: Design Considerations and Operating Experience. Transactions of the Vacuum Metallurgy Conference. Pp. 220-226. American Vacuum Society, Boston, Mass. Cannon, W. R., J. S. Haggerty, and R. A. Marra. 1982. Sinterable Ceramic Powders from Laser-Driven Reactions: I, Process Description and Modeling. Journal of the American Ceramic Society 65(7):324-330. Caputo, A. J. and W. J. Lackey. 1984. Fabrication Fiber-Reinforced Ceramic Composites by Chemical Vapor Infiltration. Ceramic Engineering Science Proceedings 5(7-8):654-667. Cannon, W. R., S.C. Danforth, J. H. Flint, J. S. Haggerty, and R. W. Marra. 1982. Sinterable Ceramic Powders from Laser-Driven Reactions: I. Process Description and Modeling. Journal American Ceramic Society 65(7):324-330. Colmet, R., I. Lhermitte-Sebire, and R. Naslain. 1986. Alumina Fiber/Alumina Matrix Composites Prepared by a Chemical Vapor Infiltration Technique. Advanced Ceramic Materials, 1(2):185-191.

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems Copley, S. M. 1985. Laser Applications. Handbook of High Speed Machining Technology. R. I. King, ed. pp. 387-416. Chapman and Hall, New York. Copley, S. M. 1986. Laser Machining. Encyclopedia of Materials Science and Engineering. Vol. 4, pp. 2511-2512. Pergamon Press, Elmsford, New York. Cornie, J. A., Y. Chiang, D. R. Uhlmann, A. Mortensen, and J. M. Collins. 1986. Processing of Metal and Ceramic Matrix Composites. American Ceramic Society Bulletin 65(2):293-304. Cranmer, D.C. 1989. Fiber Coating and Characterization. American Ceramic Society Bulletin 68(2):415-419. Deckard, C., and J. J. Beaman, 1989. Progress in Selective Laser Sintering. Paper presented at the 15th Conference on Production Research Technology, University of California at Berkeley, Jan. 9-13. Deitz, D. 1990. Stereolithography Automates Prototyping. Mechanical Engineering 112(2):34-39. Eastman, J., and R. W. Siegel. 1989. Nanophase Synthesis Assembles Materials from Atomic Clusters. Research and Development 31:56-60. Farmer, S., C. P. Pirouz, and A. H. Heuer. 1988. Microstructural Characterization of a SiC Whisker-Reinforced HIPped Reaction-Bonded Si3N4, in High Temperature/High Performance Composites. Materials Research Society Symposium Proceedings, Vol. 120, pp. 169-174. Favry, Y., and A. R. Bunsell. 1987. Characterization of Nicalon (SiC) Reinforced Aluminum Wire as a Function of Temperature. Composite Science and Technology 30:85-97. Fieldler, H. C., T. F. Sawyer, R. W. Kopp, and A. G. Leatham. 1987. The Spray Forming of Superalloys. Journal of Metals 39(8):28-33. Fitzer, E., and R. Gadow. 1986. Fiber-Reinforced Silicon Carbide. American Ceramic Society Bulletin 65(2):326-335. Granquist, C. G. 1989. Spectrally Selective Surfaces for Heating and Cooling Applications . SPIE Optical Engineering Press Tutorial Series. Bellingham, WA. Gulden, T.D. 1986. Coated Particle Fuels for High Temperature Gas-Cooled Reactors. Encyclopedia of Materials Science and Engineering. M.D. Bever, ed., p. 684. Pergamon Press, New York. Gulden, T. D., J. Chin, and L. D. Thompson. 1990a. Ambient and Elevated Temperature Mechanical Properties of Carbon T300 Fiber Reinforced Silicon Nitride Composites. 14th Annual Conference on Composites and Advanced Ceramics, Cocoa Beach, Fla., Jan. 14-17. American Ceramic Society, Westerville, Ohio. Gulden, T. D., J. E. Sheehan, and L. D. Thompson. 1990b. Fabrication and Mechanical Behavior of Mullite Fiber Reinforced Amorphous Silicon Nitride Matrix Composites Using Chemical Vapor Infiltration. 14th Annual Conference on Composite Materials and Structures. Cocoa Beach, Fla., Jan. 17-19. American Ceramic Society, Westerville, Ohio.

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems Haggerty, J. S., G. Garvey, J. M. Lirhmann, and J. E. Ritter. 1986. Processing and Properties of Reaction-Bonded Silicon Nitride Made from Laser-Synthesized Powders. Materials Research Society Symposium Proceedings, Vol. 60, pp. 51-61. Materials Research Society, Pittsburgh, Pennsylvania. Hambold, A., H. S. Shim and F. J. Schoen. 1981. Carbon in Medical Devices . Biocompatibility of Clinical Implant Materials. D. F. Williams, ed., Vol. 2. CRC Press, Boca Raton, Fla. Hayashi, C., R. Veda, and A. Tezaki. 1988. Ultrafine Particles Exploratory Science and Technology. MITA Publishers, Tokyo, Japan (in Japanese). Hayashi, C. 1987. Ultrafine particles. Journal of Vacuum Science and Technology A5(A):1375. Holland, L. 1966. Vacuum Deposition of Thin Films. Chapman and Hall, London. Hopkins, G. R., P. W. Trester, and J. L. Kaae. 1984. Experience with C + SiC Alloy Coated Armor/Limiter Tiles in Doublet III. Journal of Nuclear Material 122:1165-1169. Hughes, J. L. 1974. Making Alloy Foils by Electron Beam Evaporation. Metals Engineering Quarterly Feb.:1-5. Hull, C. W. 1986. Apparatus for Production of Three-Dimensional Objects by Stereolithography. U.S. Patent 4,575,330. Hwan, L., W. S. William, and F. Galasso. 1988. Synthesis and Characterization of SiC-Reinforced Silicon Composites Produced by Chemical Vapor Deposition. Advanced Ceramic Materials 3(6):584-589. Iga, K., Y. Kokubun, and M. Oikawa. 1984. Fundamentals of Microoptics. Academic Press, New York. Johnson, D. W. 1987. Innovations in Ceramic Powder Preparation. Advances in Ceramics. G. L. Messing, ed., Vol. 21, pp. 3-20. American Ceramic Society, Westerville, Ohio. Johnson, W. L. 1986. Thermodynamic and Kinetic Aspects of the Crystal to Glass Transformation in Metallic Materials. Progress in Materials Science 30:81-134. Kaae, J. L., and T. D. Gulden. 1971. Structure and Mechanical Properties of Codeposited Pyrolytic C-SiC Alloys. Journal of the American Ceramic Society 54:605. Kashu, S., M. Nagase, C. Hayashi, N. Wada, A. Takai, and R. Veda. 1974. Gas Condensation Technology. Proceedings of the 6th International Congress, p. 491. Vacuum Society of Japan. Tokyo, Japan. Kato, A. 1987. Vapor Phase Synthesis of Ceramic Powders. Advances in Ceramics. G. L. Messing, ed., Vol. 21, pp. 181-182. American Ceramic Society, Westerville, Ohio. Kato, A., and N. Tamari. 1980. Some Common Aspects of the Growth of TiN, ZrN, TiC, and ZrC Whiskers in Chemical Vapor Deposition. Journal of Crystal Growth 49:199-203. Kato, A., M. Yasunaga, and N. Tamari. 1977. Growth Rate of Titanium Carbide Whiskers in Chemical Vapor Deposition. Journal of Crystal Growth 37:293-300.

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems Kerans, R. J., R. S. Hay, and N. J. Pagano. 1989. The Role of the Fiber-Matrix Interface in Ceramic Composites. American Ceramic Society Bulletin 68(2):429-442. Koyama, T., and M. Endo. 1972. Carbon Fibers Obtained by Thermal Decomposition of Vaporized Hydrocarbons. Japan Journal of Applied Physics 11(4):445-449. Koyama, T., and M. Endo. Oct. 22, 1983. Japanese Patent No. 1982-58966. Lamicq, P. J., G. H. Bernharhart, M. M. Dauchier, and J. G. Mace. 1986. SiC/SiC Composite Ceramics. American Ceramic Society Bulletin 65(2):336-338. Lancin, M., J. S. Bour, and J. Thibault-Desseaux. 1988. HREM Characterization of the Interface in a SiC Fiber/Ti Matrix Composite. High Temperature/High Performance Composites, Materials Research Society Symposium Proceedings, Vol. 120, pp. 351-356. Materials Research Society, Pittsburgh, Pennsylvania. Lashmore, D. S., W. A. Jesser, D. M. Schladitz, H. J. Schladitz, and H. G. F. Wilsdorf. 1977. Microstructural Investigation of Polycrystalline Iron Whiskers. Journal of Applied Physics 48(2):478-480. Lechoczsky, S. L. 1978. Strength Enhancement in Thin-Layered Al-Cu Laminates. Journal of Applied Physics 49:5479-5485. Lee, M., and M. P. Borom. 1988. Rapid Rate Sintering of Al2O3-TiC Composites for Cutting-Tool Applications. Advanced Ceramic Materials 3(1):38-44. Lee, J. G., and I. B. Cutler. 1975. Formation of Silicon Carbide from Rice Hulls. American Ceramic Society Bulletin 54(2):195-198. Levitt, A. P. 1970. Whisker Technology. Wiley-Interscience, New York. MacLeod, H. A. 1986. Thin Film Optical Filters. MacMillan Publishing Co., New York. Mahrabian, R. 1988. New Pathways to Processing Composites. High Temperature, High Performance Composites, Materials Research Society Symposium Proceedings, Vol. 120, pp. 3-21. Maissel, L. E., and R. Glang. 1970. Handbook of Thin Film Technology. McGraw-Hill Book Co., New York. Marra, R. A., and J. S. Haggerty. 1987. Crystal Structure of Silicon Powders Produced from Laser-Heated Silane. Journal of the American Ceramic Society 70(1):c-a5-c-17. Marzik, J. V. 1984. CVD Fibers. Metal and Ceramic Matrix Composite Processing Conference at Battelle Memorial Institute, Columbus, Ohio, Nov. 13-15. Mazumder, J. 1983. Laser Welding. Lasers for Materials Processing. M. Bass, ed., Vol. 3, pp. 113-200. North-Holland Publishing Co., New York. Milewski, J. V. 1986. Efficient Use of Whiskers in the Reinforcement of Ceramics. Advanced Ceramic Materials 1(1):36-41.

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems Milewski, J. V., F. D. Gac, J. J. Petrovic, and S. R. Skaggs. 1985. Growth of Beta-Silicon Carbide Whiskers by the VLS Process. Journal of Materials Science 20:1160-1166. Millberg, L. S. 1987. The Search for Ductile Ceramics. Journal of Metals 39(11):10-13. Miller, S. E., and I. Kaminow. 1984. Optical Fiber Telecommunications II. Academic Press, New York. Mocvhan, B. A., and R. F. Bunshah. 1982. Structure Property Relationships in Microlaminate Condensates. Proceedings of the 7th International Conference on Vacuum Metallurgy, Iron & Steel Institute of Japan. Tokyo, Japan. Mortensen, A., J. A. Cornie, and M. C. Flemmings. 1988. Solidification Processing Metal-Matrix Composites. Journal of Metals 40(2):12-19. Narayan J., V. P. Godbole, and C. W. White. 1991. Laser Method for Synthesis and Processing of Continuous Diamond Films on Nondiamond Substrates. Science 252(5004):416-418. Naslain, R., H. Hannache, L. Heraud, J. Rossignol, F. Christin, and C. Bernard. 1983. Ereuo-CVD-Four. Eindhoven, Netherlands. National Materials Advisory Board-454. 1989. Research Opportunities for Materials with Ultrafine Microstructures. National Research Council, Washington, DC. Newkirk, L. R. 1981. Chemical Vapor Deposited Coatings. H. O. Pierson, ed., p. 82. American Ceramic Society, Columbus, Ohio. Nutt, S. R. 1988. Microstructure and Growth Model for Rice-Hull-Derived SiC Whiskers. Journal of the American Ceramic Society 71 (3): 149-156. Oberlin, A., M. Endo, and T. Koyama. 1976. Filamentous Growth of Carbon Through Benzene Decomposition. Journal of Crystal Growth 32(3):335-349. Oliver, W. C., R. Hutchings, and J. B. Pethica. 1984. The Wear Behavior of Nitrogen-Implanted Metals. Metallurgical Transactions 15A:2221. Osgood, R., S. R. J. Brueck, and H. R. Schlossberg (eds.). 1983. Materials Research Society Symposium 17 Proceedings. North-Holland Publishing Co., New York. Petrovic, J. J., J. V. Milewski, and F. D. Gac. 1985. Tensile Mechanical Properties of SiC Whiskers. Journal of Materials Science 20:1167-1177. Prewo, K. M. 1989. Fiber-Reinforced Ceramics: New Opportunities for Composite Materials. American Ceramic Society Bulletin 68(2):395-400. Radhakrishna, M. C., H. J. Doerr, C. V. Deshpandey, and R. F. Bunshah. 1988. Microlaminate Composites as Thermal Barrier Coatings. Surface and Coating Technology 36:143. Rhodes, J. F. 1985. ARCO SiC Whisker-Reinforced Al2O3. Paper presented at Gorham HIPing Conference, April 14-16. Monterey, Calif.

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems Rice, G. W. 1987. Laser Synthesis of Powders. Advances in Ceramics. G. L. Messing, ed., Vol. 21, pp. 229-236. American Ceramic Society, Westerville, Ohio. Rothman, E. P., J. P. Clark, and H. K. Bowen. 1986. Ceramic Cutting Tools: A Production Cost Model and an Analysis of Potential Demand. Advanced Ceramic Materials. 1(4):325-331. Sauer, W. L. 1986. Ion Implantation of Ti-6Al-4V Surgical Alloy for Improved Performance in Total Joint Prothesis. M. S. Thesis, Massachusetts Institute of Technology, Department of Material Sciences (unpublished). Schladitz, H. J. 1968. Über einige Eigenschatten yon Polykristallinen Metallfaden. Zeitz Metallkunde 59:18-22. Shim, H. S., and F. J. Schoen. 1974. The Wear Resistance of Pure and Silicon-Alloyed Isotropic Carbon. Biomaterials for Medical Devices and Artificial Organs 2:103. Singh, J. P., K. C. Goretta, D. S. Kupperman, J. L. Routbort, and J. F. Rhodes. 1988. Fracture Toughness and Strength of SiC Whisker-Reinforced Si3N4 Composites. Advanced Ceramic Materials 3(4):357-360. Sioshansi, P. 1989. Surface Modification of Industrial Components by Ion Implantation. North-Holland Publishing Co., Physics Publishing Division, New York. Sioshansi, P. 1988. Surface Engineering by Ion Implantation. Precision Metallurgy. Penton Publishing, Inc., Cleveland, Ohio. Sioshansi, P. 1987. Tailoring Surface Properties by Ion Implantation. Materials Science and Engineering 90:373. Smidt, F. A. 1990a. Surface Modification. Advanced Materials and Processes 137(1):61-62. Smidt, F. A. 1990b. Use of Ion Beam Assisted Deposition to Modify the Microstructure and Properties of Thin Films. International Materials Review 35(2):61-128. Spear, K. E. 1989. Diamond-Ceramic Coating of the Future. Journal of the American Ceramic Society 73:171. Steen, W. M., and K. M. Kamalu. 1983. Laser Cutting. Lasers for Materials Processing. M. Bass, ed., Vol. 13, pp. 15-111. North-Holland Publishing Co., New York. Suh, T. G., D. M. Umarjee, S. Prakash, H. J. Doerr, C. V. Deshpandey, and R. F. Bunshah, 1991. Preparation of Cu and SnO2 particles by DC Magnetron Sputtering. Thin Solid Films (to be published). Suplinskas, R. J., and T. W. Henze. 1982. Silicon Coated Silicon Carbide Filaments and Method. Feb. 16. U.S. Patent 4,315,968 (AVC0). Tai, N., and T. Chou. 1988. Theoretical Analysis of Chemical Vapor Infiltration in Ceramic/Ceramic Composites. High Temperature/High Performance Composites: Materials Research Symposium Proceedings, Vol. 120, pp. 185-192. Materials Research Society, Pittsburgh, Pennsylvania.

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems Tamari, N., and A. Kato. 1979. Catalytic Effects of Various Metals and Refractory Oxides on the Growth of TiC Whiskers by Chemical Vapor Deposition. Journal of Crystal Growth 46:221-237. Tang, D. Y., R. K. Route, and R. S. Feigelson. 1988. Growth of Barium Metaborate Single Crystal Fibers by the Laser-Heated Pedestal Growth Method. Journal of Crystal Growth 91:81-89. Tao, H. Y., W. Chang, S. M. Copley, and J. A. Todd. 1989. Effect of Surface Treatment on the Strength of Laser Machined Silicon Nitride. Laser Materials Processing III. J. Mazumder and K. N. Mukherjee, eds., pp. 199-215. Minerals, Metals & Materials Society, American Institute of Mining, Metallurgical and Petroleum Engineers, New York. Tennery, V. J. 1989. Ceramics in Engines—An International Status Report. American Ceramic Society Bulletin 68(2):362-365. Theis, J. D., Jr. 1972. Third International Conference on Chemical Vapor Deposition. F. A. Glaski, ed., p. 561. American Nuclear Society, Hinsdale, Ill. Thylen, L. 1988. Integrated Optics in LiNbO3; Recent Developments in Devices for Telecommunications. Journal of Lightwave Technology 6:847-861. Tibbetts, G. G. 1989. Vapor-Grown Carbon Fibers: Status and Prospectus. Carbon 27(5):745-747. Tiegs, T. N., and P. F. Becher. 1985. SiC Whisker-Reinforced Ceramic Composites. 9th Annual Conference on Composites and Advanced Materials, January, Cocoa Beach, Fla. American Ceramic Society, Westerville, Ohio. Tsangarakis, N., B. O. Andrews, and C. Cavallero. 1987. Mechanical Properties of Some Silicon Carbide Reinforced Aluminum Composites. Journal of Composite Materials, 21:481-492. Veprek, S., M. Heintze, F. Mattenberger, W. Portmann, D. Ringer, and U. Stiefel. 1989. Large Scale In Situ Coatings of Boron Carbide for Tokamak Controlled Fusion Devices. Proceedings of the 9th International Symposium on Plasma Chemicals. R. d'Aggostino, ed., p. 1671. Sept. 4-8, Pungochiuso, Italy. Wallace, R. J., and S. M. Copley. 1989. Shaping Silicon Nitride with a Carbon Dioxide Laser by Overlapping Multiple Grooves. ASME Journal of Engineering for Industry 111:3115-3121. Wokulski, Z., and K. Wokulska. 1983. On the Growth and Morphology of TiCx Whiskers. Journal of Crystal Growth 62:439-446. Wu, H. F. and A. J. Perrotta. 1991. Screening Characterization on the Strength and Strain of Single Crystal a-A12O3 Fibers Grown by Laser-Heated Pedestal Technique. Light Metals Age, 49(3,4):April 97-98. Yajima, S. 1980. Development of Ceramics, Especially Silicon Carbide Fibers, from Organosilicon Polymers by Heat Treatment. Philosophical Transactions of Royal Society, London. A294:419-426.

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Beam Technologies for Integrated Processing - Report of the Committee on Beam Technologies: Opportunities in Attaining Fully-Integrated Processing Systems Yang, L., and R. G. Hudson. 1967. Evaluation of Chemical Vapor Deposited Tungsten as Electron Emitters for Nuclear Thermionic Application. Proceedings of the Conference on Chemical Vapor Deposition of Refractory Metals, Alloys and Compounds. A. C. Schaffhauser, ed., pp. 329-348. American Nuclear Society, Hinsdale, Ill. Zanchuk, W. A. 1988. Fiber-Reinforced, High Performance Alloys. Journal of Metals 40(5):52-53. Znotins, T. A., D. Poulin, and J. Reid. 1987. Excimer Lasers: An Emerging Technology in Materials Processing. Laser Focus/Electrooptics 23(5):54-70.

Representative terms from entire chapter:

ceramic society