Anomalous Changes in Electric Conductivity of Cu-Phthalocyanine Observed During Evaporation Process

Abstract

The in-situ measurement of lateral electric conductivity of copper phthalocyanine was conducted during a vacuum evaporation process. The conductivity was found to change anomalously at the first stage of film growth. With increasing thickness, it increased abruptly from about 2 nm in film thickness, and showed a sharp peak at about 7 nm. Even if the evaporation rate or the sample purity was varied, the similar behavior was observed. Possible reasons for this anomalous phenomenon are discussed from the structural changes and molecular motion occurring during the growth process of the evaporation films.