Investigation of molecular chains structure of polyimide Langmuir–Blodgett films by atomic force microscopy

Atomic force microscopy was applied to investigate the microscopic molecular structures of polyimide Langmuir–Blodgett (LB) films. The polyimide chains of a monolayer film on graphite were observed. It was found that the polyimide LB film with a groovy surface occurs due to the orientation of polyimide chains. By horizontal deposition the polyimide chains show a zigzag structure, while by vertical deposition the polyimide chains show a straight‐line structure. Moreover, the polyimide chains are always oriented along the direction of deposition. It is suggested that the polyimide chains are oriented by the LB technique.