| 초록 |
For the application to the low dielectric insulating materials, nanoporous organosilicate materials should have low dielectric constant (k ＜ 2.2) as well as sufficient mechanical properties, since low dielectric films have to withstand severe down pressure and shear force during chemical mechanical polishing process. However, the detailed characterization of mechanical properties for nanoporous films are not carried out. Here, we investigated elastic modulus, hardness, and dissipation energy ratio of nanoporous organosilicate thin films to examine the effect of porosities on the mechanical properties. With increasing porosities, elastic modulus and hardness decreased. Dissipated energy ratio, which is the ratio of elastic deformation, increased, since the plastic deformation such as cracks and pore collapse became dominant due with increase in the porosity. Nanoporous films were prepared from the copolymerized methylsilsesquioxane(MSSQ) and tetra functional block copolymer. |
