Effects of crystallinity in spin-on pure-silica-zeolite MFI low-dielectric-constant films

Low-dielectric-constant (low-kappa) materials are a critical requirement for future generations of computer microprocessors. As a unique class of porous silicas, pure silica zeolites (PSZs) have been shown to be a promising low-kappa material with excellent mechanical strength (e.g., elastic modulus of 16-18 GPa) due to their crystalline nature. In the present study, we show for the first time that higher crystallinity of spin-on PSZ MFI films leads to lower kappa values and less moisture sensitivity - two critical properties of a porous low-kappa material. We have also advanced the two-stage synthesis method to produce zeolite nanoparticles with high yield (77%) and a small diameter (<80 nm). A kappa value of 1.6 is obtained from the silylated highly crystalline PSZ MFI film and the kappa value only increases by 12.5% after exposure to ambient conditions for a period of 24 h.