| 초록 |
Novel polymethylsilsesquioxane (PMSSQ) based materials suitable for ultra-low-dielectric (ultra-low-k, k＜2.2) film applications for high performance microelectronic devices were prepared by terpolymerization of methyltrimethoxysilane (MTMS), 1,2-bis(triethoxysilyl)ethane (BTESE) and a synthesized triethoxysilane with covalently linked thermally volatile polypropylene oxide (PPO) units. The refractive index of the films decreased in proportion to the fraction of thermally volatile PPO part in the terpolymers. The critical structural information such as average pore size and interconnectivity were deduced by positronium annihilation lifetime spectroscopy (PALS) experiments. Modulus and hardness of cured films were evaluated by nanoindenter. The superior mechanical properties with smaller pore sizes were observed as comparing to the nanoporous films having same porosities produced by blending approach. |
