Dielectric materials preparation

Another method that has great potential for the preparation of advanced prepregs and has been explored extensively requites fine powders. The reinforcing fibers are coated with fine particles of the resin and, when heated, the resin flows over the fiber. This method requites finely divided particles either in aqueous solution, in an inert volatile solvent, or as high dielectric material that can be charged and coated by electrostatic attraction to the fiber. Synthetic methods that make fine particles, similar to that described for PEEK (23), are needed. 

Material Preparation method Deposition temperature [°C] Dielectric constant Refs... 

You [4] prepared porous thermoset dielectric materials having low dielectric constants which were used in electronic component manufacture with cross-linked polymeric porogen particles as provided in Table 2. 

TABLE 1. Components used in preparing porogen particles which were compatible with the B-staged henzocyclohutene dielectric materials after crosslinking with 10% trimethylol-propane triacrylate. 

With the progress in microwave telecommunication technology, dielectric materials have come to play an important role in the miniaturization and compactness of microwave passive components. The dielectric materials available for micro-wave devices are required to have predictable properties with respect to a high dielectric constant (K), high quality factor (Qf), and small temperature coefficient of resonant frequency (TCP). Numerous microwave dielectric materials have been prepared and investigated for their microwave dielectric properties and for satisfying these requirements. In particular, complex perovskite compounds A(B,B )03... 

In this review, nanoporous dielectric materials have been presented. The preparation techniques, methods of pore generation, and materials classification were discussed. Inorganic, organic, and hybrid films were also discussed. The nanoporous dielectric films were classified by preparation method, which includes block copolymer, solvent as porogen approach, surfactant templating, and sol-gel approach. This is still a very active field of research because no one film has satisfied all the stringent requirements in semiconductor device processing. 

Many intensive scientific investigations are focused on the preparation and characterisation of new polymeric organic films. Many newer surface science techniques, designed and developed for semiconductors and dielectric materials, address specific details about the structure and morphology of these organic films. 

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