Improved ohmic contacts on pentacene based on Au with ultraviolet irradiation treatment

The effect of ultraviolet irradiation treatment on a reduction in contact resistivity at the pentacene/Au interfaces was investigated using current-voltage and X-ray photoelectron spectroscopy in this study. The contact resistivity was drastically decreased from 2.2 × 10⁷ to 9.5 × 10² Ω cm² by the treatment. We suggested that the lower contact resistivity of the pentacene/Au sample with ultraviolet irradiation treatment than the pentacene/Au sample without ultraviolet irradiation treatment may be attributed to the heightened conductivity of pentacene near the pentacene/Au interface resulting from the incorporation of oxygen (from the Au surfaces with ultraviolet irradiation treatment) in pentacene near the interface.