Estimation of phase separation behavior in nanohybrids by thermal and dielectric analyses

The compatibility between low-k matrix and porogen was characterized by TGA and dielectric analyses. A new low-k matrix has been prepared by copolymerization of methyl trimethoxysilane (MTMS) with [bis(1,2-trimethoxysilyl)ethane, BTMSE 10%] to control its compatibility with porogens. The shift of both decomposition and glass transition temperature (Tg) of porogen in hybrids was dependent on the content of porogen. As porogen loading increased over critical points, decomposition temperature and Tg of porogen in hybrids approached the corresponding temperature of porogen itself, which implied that large domains as well as nanoscopic domains were formed. In addition, these critical points were much higher for MSSQ copolymer than MSSQ, which meant that MSSQ copolymer produced the smaller pores than MSSQ due to better compatibility. This was also verified by comparing the cross-sectional FE-SEM images of both porous MSSQ and MSSQ copolymer.