Carrier Mobility of Pyrolyzed Polyimide Films

Publisher Website
Google Scholar
Abstract
The carrier mobility of pyrolyzed polyimide films was estimated by the time-of-flight technique. The carrier mobility could be estimated for the polyimides pyrolyzed between 480 and 530°C, which possessed conductivities between 10-12 and 10-8 S cm-1 and mobilities ranging from 10-7 to 10-3 cm2V-1s-1. The number of carriers connected with charge transport remained unchanged even when the pyrolysis temperature was varied from 490 to 530°C, as the conductivity was proportional to the mobility. In polymides pyrolyzed at lower temperatures, below 490°C, a deviation from the close relation between the mobility and the conductivity was observed. These results suggest that the carrier density increases at the initial stage of the pyrolysis, and then the increase of the mobility becomes predominant as the pyrolysis progresses.