The current-voltage characteristics on field emission through a four-leaf pattern, a two-leaf pattern and a single large bright spot of adsorbed Cu- and Co-phthalocyanines on a tungsten tip have been measured, and Fowler-Nordheim (FN) plots of field emission were obtained. The slopes of the FN plots for the four-leaf patterns were almost equal to or even a little higher than those for the substrate surface. In contrast, the slopes of the two-leaf patterns were about 10–15% lower than those of the substrate surface and the slopes of the single bright spots were about 20–25% lower.

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