Fabrication of n-buffer layers in organic devices by friction-transfer method

ABSTRACT

The buffer layers, which are inserted between electrodes and active layers, are important for improving organic devices, e.g., photovoltaic (OPVs) or light emitting devices (OLEDs). An amine-substituted polyfluorene, PFN-P1, is used as an n-type buffer material, transporting electron, which is inserted between cathodes and active layers. In this study, we tried to fabricate n-buffer layers of PFN-P1 by friction transfer that is film coating method using no solvent. PFN-P1 thin layers on ITO substrates could be prepared by friction transfer method. We fabricated inverted OPVs with friction-transferred n-type buffer layers. The device structure is Ag/PEDOT:PSS/ PTB7:PCBM/PFN-P1/ITO. This device showed a comparable performance with a device with spin-coated PFN-P1. We also fabricated MEH-PPV-based inverted OLED using a friction-transferred PFN-P1.

KEYWORDS:

• Buffer layers
• electroluminescence
• friction-transfer method
• photovoltaic devices
• thin films

Funding

This study was partly supported by New Energy and Industrial Technology Development Organization (NEDO).