Deposition of organic-inorganic hybrid polymer thin films with a silsesquioxane unit

Thin films of 3-methacryloyloxypropylheptaisobutyl-T8-silsesquioxane (BuPOSSMA) were prepared by an electron-assisted (e-assist) deposition method. The film deposited by the conventional vapor deposition without the e-assist had a polycrystalline structure with a rough surface, whereas the e-assist deposition produced amorphous polymer thin films with a smooth surface. The deposited films were electrically insulating with a breakdown strength higher than 2 x 10(6) V cm(-1). The polymerization of BuPOSSMA resulted in a decrease in the dielectric constant of the film. It was found that the deposition-polymerization achieved by the e-assist is effective in improving the thermal stability of the insulating and dielectric characteristics.