Thin films processing

The ability to apply a planarizing, optically transparent, thermally stable polymer system that cures under relatively mild conditions has recently been demonstrated to have utility in the fabrication of multilayer devices such as advanced color liquid-crystal display The ability to apply this material as a dielectric or optical coating for thin-film electronics devices has also recently been demonstrated with the fabrication of an optical wave guiding device.  

A new method for the syntheses of fluorocarbon polyarylate polymers has been demonstrated. The chemistry utilizes the [27t+27t] cyclodimerization of fluorinated olefins and generates polymers of novel composition. The first generation of polymers prepared by this method are polyarylate homopolymers. Theremoplastic polymers of high molecular weight can be achieved via neat or solution polymerization. One example of a thermoset polymer prepared by this method has a high Tg, low dielectric constant and dissipation factor, low moisture 

A variety of polymer compositions that use this type of polymerization chemistry can be envisioned. In addition to the polyarylate homopolymers that have been described in this chapter, random or block copolymers can be prepared with reasonable ease by the combination of different monomers or oligomers. These compositions can be designed to optimize thermal, mechanical, dielectric, or optical properties of a polymer system. Also, the trifluorovinyl ether functionality can be incorporated into other high-performance polymer systems with relative ease. - The perfluorocyclobutane polyarylate chemistry is a versatile approach to the preparation of high-performance polymers, which is just beginning to demonstrate its utility. 

Acknowledgments Many Dow researchers have contributed their time and talents to the chemistry and analytical data presented in this manuscript. A complete list of the contributors is not practical, but a few individual recognitions 

Cassidy, L. A. Hoelscher, andD. L. Meuer, 5th Intern. SiElectronics Conf 

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Vossen J L and Kern W (eds) 1991 Thin Film Processes II (San Diego, CA Academic)... 

As with ah thin-film PV technologies, the projected manufacturing costs of a-Si H ahoy PV modules fah rapidly with annual manufacturing volume, ie, MWp /yr. The primary driver of this volume cost reduction is the volume—cost relationship of commercially available thin-film processing equipment. Thin-film coating machines often have capacities equivalent to 3—5 yr, so that manufacturing economies of scale are more fully realized at the... 

L. Vossen and W. Kem, eds.. Thin Film Process, Academic Press, London, 1978. 

Kern, W., and Ban, V. S., Chemical Vapor Deposition of Inorganic Thin Films, in Thin Film Processes, (J. Vossen and W. Kern, eds.). Academic Press, New York (1978)... 

The number of oxides is large since most metallic elements form stable compounds with oxygen, either as single or mixed oxides. However, the CVD of many of these materials has yet to be investigated and generally this area of CVD has lagged behind the CVD of other ceramic materials, such as metals, carbides, or nitrides. The CVD of oxides has been slower to develop than other thin-film processes, particularly in optical applications where evaporation. 

Its thin-film processing is compatible with silicon technology. 

Optoelectronics is a relatively new and fast-growing industry with many applications. Thin-film processes, such as reactive sputtering, molecular-beam epitaxy (MBE), and particularly MOCVD, play a major part in their production. Equipment and materials are similar to those used in the semiconductor industry and many companies manufacture both types of products. In fact the distinction between the two areas is often blurred. Statistics generally do not single out optoelectronics as such and, for that reason, it is difficult to define the scope of the industry accurately. 

Sputtering i s presently the maj or thin-film process for the production of deicing coatings. The coating is satisfactory from an optical standpoint although transmission could still be improved, but it has poor scratch resistance and must be sandwiched between the two layers of safety glass. The CVD oxides films shown in Table 16.1 are particularly attractive since they are inherently abrasion resistant and could be used on the outer surface of the glass. 

Sputtering is an important thin-film process used extensively in the semiconductor and hard-coating industries and for decorative and jewelry coatings. PlP] Excellent coatings of refractory compounds and metals can be readily produced with good adhesion and composition control without the high temperature requirements of CVD. 

In other cases, a thin-film process is used to form the layers. Thin-film processes used in the manufacture of IC s include ... 

GP 11] ]R 20] Investigations with a Pd membrane reactor relied on reaction of streams separated via a membrane (to prevent complete mixing of reactants, not to enhance conversion) [11]. A hydrogen/nitrogen stream is guided parallel to an oxygen stream, both separated by the membrane and water is thereby formed. The membranes, made by thin-film processes, can sustain a pressure up to 5 bar. 

E. S. Machlin, Materials Science in Microelectronics—the Relationships between Thin Film Processing and Structure. Giro Press. Croton-on-Hudson, NY, 1995. 

Schwartz, R. W. Assink, R. A. Headley, T. J. 1992. Solution chemistry effects in PZT thin film processing spectroscopic and microstructural characterization. In Ferroelectric Thin Films II, edited by Kingon, A. I. Myers, E. R. Tuttle, B. Mat. Res. Soc. Symp. Proc. 243 245-254. 

In thin film processes for microelectronic applications, we deal almost exclusively with glow discharges. These plasmas are characterized by pressures in the range of 50 mTorr to 5 Torr, electron densities between 10 and 10 cm , and average electron energies between 1 and 10 eV (such ener-... 

Metal in gap (MIG) or ferrite heads are produced with a combination of machining, bonding, and thin-film processes. Thin-film inductive heads are manufactured using thin-fihn processes similar those of semiconductor 1C technology (discussed in Chapter 19). The thin-film head production process is rather unusual, as it involves both very thin and very thick films. We choose to present here a detailed summary of the fabrication process of thin-film inductive heads with a single-layer spiral coil. This may serve, once again to, illustrate the centrally important role of electrochemical deposition in connection with modem information technology. 

Kern W, Vossen J (1991) Thin film processes II. Academic press, New York. 

Many thin-film processing techniques have been developed and further improved in the search for the most suitable approach for a specific application. Typically thin films can be prepared from either the hquid or gaseous phase. Vapour-phase deposition processes, which are more popular, fall into the two main categories of physical and chemical vapour deposition. Atomic layer deposition holds a special position among the chemical vapour deposition techniques because it offers the possibility to produce thin films in a controlled, self-hmiting manner. 

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