SURFACE CHARACTERIZATION OF ULTRA-THIN POLYIMIDE FILMS FORMED BY USING LANGMUIR-BLODGETT METHOD

The polyimide films were prepared by imidizing the polyamic acid long- chain alkylamine (dimethylhexadecylamine) salt films with a thermal tr eatment up to 300 degrees C for 30 minutes, where the polyamic acid al kylamine salt films were formed on various substrates by using Langmui r-Blodgett (LB) method. The imidization of polyamic alkylamine salt fi lms with various thickness were identified with FT-IR and UV-visible a bsorption spectroscopies. Atomic Force Microscopy (AFM) and Scanning E lectron Microscopy (SEM) have been used to investigate the surface mor phology of polyamic acid alkylamine salt and imidized films with a thi ckness from one monolayer to ten monolayers. It was found that the imi dization of the polyamic acid alkylamine salt films with a thermal tre atment significantly increases the surface microroughness of those fil ms by forming sub-micron order of polyimide grains on substrates and n o defects such as pin holes were observed by SEM analysis.