ION-BEAM-ASSISTED FORMATION OF INTERCONNECTIONS INTO HIGH-TEMPERATURE POLYMERS

High energy ion beams induce conductive properties into heat-resistant polymers due to band closing which results from the formation of extended aromatic domains. The aromatic cycles which ensure the high stability of the molecular structure promote the formation of highly conducting (102-103 s/cm) phases in these polymers upon irradiation. The field of application of this process is analyzed and we show that the main interest lies in the formation of short links such as for vertical interconnections (VIAs) in multilevel integration of circuits or in the restructuration of circuits. We discuss the main parameters which control the appearance of conductivity and emphasize the role of the ion beam flux, which is a cause of reproducibility difficulties. Some solutions are proposed. © 1990.