By thermally evaporated through a tilted shadow mask, metal vapor scatters and lands on the substrate to form an ultrathin layer. Absence of screening effect from bulk metal enables direct measurement of the buried dipole formed at the organic/metal interface. It is found that polar species of the organic, Fermi-level pinning and interface morphology can all influence the dipole orientation. The proposed method provides a quick and easy approach to assess interfacial materials and design electrode interfaces in organic electronic devices.
- Zhanhao Hu
- Zhiming Zhong
- Yong Cao
