Blue Narrowband Photomultiplication Type Organic Photodetector Using ZnPc as Photon Field Modulation Layer

Abstract

In this work, a blue narrowband photomultiplication (PM) type organic photodetector (OPD) is fabricated with ZnPc as photon field modulation layer. The photomultiplication in OPD is attributed to electron trap assisted hole injection mechanism. In PM OPD, ZnPc altered the distribution of photogenerated charge carriers within the P3HT:PCBM active layer and results in narrowband detection. This study is the first to demonstrate a narrowband PM OPD with a peak response at 480 nm, using a P3HT:PCBM active layer. The detector demonstrated a rejection ratio (EQE_{480 nm}/EQE_{570 nm}) of 590, and a full width half maximum (FWHM) of 67 nm with 1000 nm thick ZnPc as photon field modulation layer. As the ZnPc layer thickness is increased from 200 nm to 1500 nm, the FWHM of the detector narrowed from 175 nm to 67 nm. The demonstrated narrowband photodetector with response peak in blue region has diverse applications in communication and imaging fields.