Applying zeolites as low dielectric constant (low-k) materials

Low-dielectric-constant (low-k) materials are essential for the development of future generation faster and cheaper computer microprocessors. The actual progress toward the development of a successful low-k material has thus far been much slower than desired because of the stringent requirements of electrical, mechanical, chemical, and interfacial properties. The low-k materials used in the-state-of-the-art chips are carbon-doped silica, which could have a k-value as low as 2.7, but materials with much lower k-value (e.g., k <2.2) are needed.;Pure-silica-zeolites (PSZs) have been investigated as possible low-k materials, which have the advantages of superior mechanical strength, uniform microporosity, high heat conductivity, as well as high hydrophobicity over other porous silica-based low-k materials. From this point, there are two pathways to solve low-k problem faced by semiconductor industry. One way is to optimizing present spin-on low-k films from PSZ nanoparticle suspension. The other way is to better zeolite framework structures than MFI and MEL. No matter which way, there are some fundamental issues need to be thoroughly understood, such as the influence of aluminum atoms in zeolite framework, and the effect of nanocrystals size and content of defects, which can both affect the dielectric properties significantly.;In this dissertation, PSZ nanocrystal suspension synthesis was optimized by developing an evaporation-assisted two-stage method to obtain smaller crystal size with keeping high yield, which resulted smoother films with higher mechanical strength. Furthermore, a new dielectric constant measurement method was introduced to screen through different zeolite frameworks for better low-k candidates. PSZ LTA was demonstrated to be promising low-k material. Moreover, the bulk dielectric constant of zeolites with different aluminum content and zeolite nanocrystals of different sizes were measured. Such fundamental studies provided important information for us to pursue better zeolite low-k materials and optimize preparation processes. As a result of the scientific and engineering work in this dissertation, PSZ low-k films have been proven a leading low- k candidate and high potential for further research.