XPS Study of Polyimide H‐Film after Heat‐Treatment and Laser Processing

Insulating Kapton® H‐film can be made electrically conducting by heat‐treatment in vacuum or by intense laser irradiation in air. The nearly metallic behavior of Kapton after heat‐treatment at 700°C has attracted scientific interest in the material. We report an XPS study of the polyimide after heat‐treatment and laser processing. The carbon, oxygen, and nitrogen binding energies and their evolution with increasing temperature of heat‐treatment have been examined. Comparison is made with pristine and laser‐irradiated polyimide. The carbon, oxygen, and nitrogen spectra undergo significant changes at different processing temperatures. We find that the ether oxygen and the carbonyl carbon are affected at a lower processing temperature than the nitrogen bonds. The laser and heat‐treated products are not identical and they are not pure carbon residues.